Schedule

Investments

Principal

Active

High

Yield

ETF

March

31,

2024

(unaudited)

See

accompanying

notes.

BONDS

.07

Principal

Amount

Value

Aerospace

Defense

.34

—

Bombardier,

Inc.

7.25%,

07/01/2031

(a)

290,000‌

290,590‌

7.50%,

02/01/2029

(a)

820,000‌

844,382‌

8.75%,

11/15/2030

(a)

1,072,000‌

1,144,656‌

2,279,628‌

Airlines

.05

United

Airlines

Pass-Through

Trust

Series

2016-

Class

3.65%,

07/07/2027

86,529‌

82,325‌

Auto

Parts

Equipment

.05

Dana,

Inc.

4.25%,

09/01/2030

1,735,000‌

1,533,113‌

Phinia,

Inc.

6.75%,

04/15/2029

(a)

115,000‌

116,109‌

Tenneco,

Inc.

8.00%,

11/17/2028

(a)

2,010,000‌

1,834,001‌

3,483,223‌

Banks

.90

Barclays

PLC

(5-year

Treasury

Constant

Maturity

Rate

5.43%),

8.00%,

03/15/2029

(b),(c)

2,416,000‌

2,411,021‌

JPMorgan

Chase

Co.

Series

(3-month

Term

Secured

Overnight

Financing

Rate

3.13%),

4.60%,

02/01/2025

(b),(c)

2,556,000‌

2,512,838‌

4,923,859‌

Building

Materials

.89

AmeriTex

HoldCo

Intermediate

LLC

10.25%,

10/15/2028

(a)

2,283,000‌

2,451,157‌

Smyrna

Ready

Mix

Concrete

LLC

6.00%,

11/01/2028

(a)

2,518,000‌

2,460,985‌

4,912,142‌

Chemicals

.47

Consolidated

Energy

Finance

5.63%,

10/15/2028

(a)

1,625,000‌

1,363,764‌

12.00%,

02/15/2031

(a)

815,000‌

851,153‌

Kobe

U.S.

Midco

Inc.

9.25%,

PIK

10.00%,

11/01/2026

(a),(d)

2,218,650‌

1,891,399‌

Olympus

Water

U.S.

Holding

Corp.

6.25%,

10/01/2029

(a),(e)

2,730,000‌

2,498,760‌

Tronox,

Inc.

4.63%,

03/15/2029

(a)

1,107,000‌

992,908‌

7,597,984‌

Commercial

Services

.36

Albion

Financing

SARL/Aggreko

Holdings,

Inc.

6.13%,

10/15/2026

(a)

1,394,000‌

1,381,263‌

Garda

World

Security

Corp.

6.00%,

06/01/2029

(a)

1,116,000‌

998,869‌

9.50%,

11/01/2027

(a)

1,449,000‌

1,452,486‌

WASH

Multifamily

Acquisition,

Inc.

5.75%,

04/15/2026

(a)

1,921,000‌

1,877,532‌

5,710,150‌

Computers

.62

McAfee

Corp.

7.38%,

02/15/2030

(a)

575,000‌

527,302‌

NCR

Atleos

Corp.

9.50%,

04/01/2029

(a)

1,505,000‌

1,609,761‌

Seagate

HDD

Cayman

5.75%,

12/01/2034

880,000‌

860,834‌

9.63%,

12/01/2032

1,284,119‌

1,462,994‌

4,460,891‌

Distribution

Wholesale

.97

Verde

Purchaser

LLC

10.50%,

11/30/2030

(a)

1,566,000‌

1,648,823‌

BONDS

(continued)

Principal

Amount

Value

Diversified

Financial

Services

.39

AerCap

Holdings

(5-year

Treasury

Constant

Maturity

Rate

4.54%),

5.88%,

10/10/2079

(c)

2,410,000‌

2,392,726‌

Credit

Acceptance

Corp.

9.25%,

12/15/2028

(a)

2,313,000‌

2,487,819‌

Global

Aircraft

Leasing

Co.

Ltd.

6.50%,

PIK

7.25%,

09/15/2024

(a),(d)

2,544,562‌

2,420,205‌

Macquarie

Airfinance

Holdings

Ltd.

8.13%,

03/30/2029

(a)

1,295,000‌

1,369,620‌

8.38%,

05/01/2028

(a)

1,363,000‌

1,444,734‌

OneMain

Finance

Corp.

3.50%,

01/15/2027

180,000‌

167,094‌

4.00%,

09/15/2030

2,254,000‌

1,929,077‌

6.63%,

01/15/2028

344,000‌

345,105‌

12,556,380‌

Electric

.23

Clearway

Energy

Operating

LLC

3.75%,

02/15/2031

(a)

2,611,000‌

2,240,995‌

GenOn

Energy,

Inc.

0.00%,

10/15/2020

(f),(g),(h)

3,100,000‌

—‌

NextEra

Energy

Operating

Partners

7.25%,

01/15/2029

(a)

785,000‌

803,183‌

NRG

Energy,

Inc.

3.63%,

02/15/2031

(a)

1,339,000‌

1,155,500‌

3.88%,

02/15/2032

(a)

161,000‌

137,967‌

(5-year

Treasury

Constant

Maturity

Rate

5.92%),

10.25%,

03/15/2028

(a),(b),(c)

327,000‌

350,776‌

Vistra

Corp.

(5-year

Treasury

Constant

Maturity

Rate

5.74%),

7.00%,

12/15/2026

(a),(b),(c)

997,000‌

987,175‌

Vistra

Operations

Co.

LLC

4.38%,

05/01/2029

(a)

1,641,000‌

1,520,197‌

7,195,793‌

Electronics

.85

Sensata

Technologies,

Inc.

3.75%,

02/15/2031

(a)

1,664,000‌

1,439,363‌

Entertainment

.71

Boyne

USA,

Inc.

4.75%,

05/15/2029

(a)

1,980,000‌

1,835,405‌

Caesars

Entertainment,

Inc.

6.50%,

02/15/2032

(a)

2,387,000‌

2,408,020‌

CCM

Merger,

Inc.

6.38%,

05/01/2026

(a)

2,243,000‌

2,240,920‌

Churchill

Downs,

Inc.

5.75%,

04/01/2030

(a)

2,431,000‌

2,346,648‌

Cinemark

USA,

Inc.

5.25%,

07/15/2028

(a),(e)

1,931,000‌

1,827,987‌

Lions

Gate

Capital

Holdings

LLC

5.50%,

04/15/2029

(a)

1,959,000‌

1,498,707‌

Wynn

Resorts

Finance

LLC/Wynn

Resorts

Capital

Corp.

7.13%,

02/15/2031

(a)

912,000‌

943,825‌

13,101,512‌

Food

.65

Chobani

LLC/Chobani

Finance

Corp.,

Inc.

7.63%,

07/01/2029

(a)

2,059,000‌

2,087,312‌

Fiesta

Purchaser,

Inc.

7.88%,

03/01/2031

(a)

390,000‌

402,753‌

Pilgrim's

Pride

Corp.

3.50%,

03/01/2032

2,073,000‌

1,756,909‌

4.25%,

04/15/2031

277,000‌

249,699‌

4,496,673‌

Forest

Products

Paper

.44

Mercer

International,

Inc.

5.13%,

02/01/2029

774,000‌

680,325‌

Schedule

Investments

Principal

Active

High

Yield

ETF

March

31,

2024

(unaudited)

See

accompanying

notes.

BONDS

(continued)

Principal

Amount

Value

Forest

Products

Paper

(continued)

Mercer

International,

Inc.

(continued)

12.88%,

10/01/2028

(a)

55,000‌

60,088‌

740,413‌

Healthcare

Services

.55

Acadia

Healthcare

Co.,

Inc.

5.00%,

04/15/2029

(a)

2,516,000‌

2,390,697‌

Tenet

Healthcare

Corp.

6.13%,

06/15/2030

1,943,000‌

1,938,543‌

4,329,240‌

Home

Builders

.24

Adams

Homes,

Inc.

9.25%,

10/15/2028

(a)

1,541,000‌

1,598,721‌

Forestar

Group,

Inc.

3.85%,

05/15/2026

(a)

362,000‌

345,707‌

5.00%,

03/01/2028

(a)

1,929,000‌

1,854,748‌

3,799,176‌

Household

Products

Wares

.99

Kronos

Acquisition

Holdings,

Inc./KIK

Custom

Products,

Inc.

5.00%,

12/31/2026

(a)

540,000‌

529,341‌

7.00%,

12/31/2027

(a)

1,170,000‌

1,162,232‌

1,691,573‌

Insurance

.16

Acrisure

LLC/Acrisure

Finance,

Inc.

6.00%,

08/01/2029

(a)

2,146,000‌

1,968,051‌

Investment

Companies

.52

Compass

Group

Diversified

Holdings

LLC

5.25%,

04/15/2029

(a)

2,147,000‌

2,039,934‌

Icahn

Enterprises

LP/Icahn

Enterprises

Finance

Corp.

4.38%,

02/01/2029

2,640,000‌

2,250,845‌

4,290,779‌

Iron

Steel

.02

TMS

International

Corp.

6.25%,

04/15/2029

(a)

1,901,000‌

1,735,120‌

Lodging

.48

Wynn

Macau

Ltd.

5.63%,

08/26/2028

(a)

868,000‌

822,713‌

Machinery

Diversified

.27

Maxim

Crane

Works

Holdings

Capital

LLC

11.50%,

09/01/2028

(a)

1,991,000‌

2,158,642‌

Media

.94

CSC

Holdings

LLC

4.50%,

11/15/2031

(a)

1,199,000‌

848,852‌

Directv

Financing

LLC

8.88%,

02/01/2030

(a)

128,000‌

127,691‌

Directv

Financing

LLC/Directv

Financing

Co.-

Obligor,

Inc.

5.88%,

08/15/2027

(a)

2,230,000‌

2,109,661‌

DISH

DBS

Corp.

5.13%,

06/01/2029

278,000‌

115,950‌

5.25%,

12/01/2026

(a)

13,284‌

10,460‌

7.38%,

07/01/2028

1,166,000‌

561,344‌

DISH

Network

Corp.

11.75%,

11/15/2027

(a)

1,640,000‌

1,674,327‌

Scripps

Escrow

II,

Inc.

5.38%,

01/15/2031

(a)

704,000‌

433,148‌

Sunrise

HoldCo

5.50%,

01/15/2028

(a)

844,000‌

810,338‌

6,691,771‌

Mining

.38

Taseko

Mines

Ltd.

7.00%,

02/15/2026

(a)

2,331,000‌

2,340,536‌

Oil

Gas

.25

Aethon

United

LP/Aethon

United

Finance

Corp.

8.25%,

02/15/2026

(a)

1,904,000‌

1,925,970‌

Civitas

Resources,

Inc.

8.63%,

11/01/2030

(a)

1,499,000‌

1,609,592‌

BONDS

(continued)

Principal

Amount

Value

Oil

Gas

(continued)

Comstock

Resources,

Inc.

5.88%,

01/15/2030

(a)

2,325,000‌

2,105,539‌

Diamond

Foreign

Asset

Co./Diamond

Finance

LLC

8.50%,

10/01/2030

(a)

1,566,000‌

1,652,769‌

Vital

Energy,

Inc.

9.75%,

10/15/2030

1,483,000‌

1,621,732‌

8,915,602‌

Oil

Gas

Services

.33

Archrock

Partners

LP/Archrock

Partners

Finance

Corp.

6.25%,

04/01/2028

(a)

1,643,000‌

1,625,646‌

Kodiak

Gas

Services

LLC

7.25%,

02/15/2029

(a)

630,000‌

641,710‌

2,267,356‌

Packaging

Containers

.40

Clydesdale

Acquisition

Holdings,

Inc.

6.63%,

04/15/2029

(a)

203,000‌

202,837‌

8.75%,

04/15/2030

(a)

725,000‌

712,341‌

LABL,

Inc.

5.88%,

11/01/2028

(a)

404,000‌

371,520‌

8.25%,

11/01/2029

(a),(e)

673,000‌

574,315‌

9.50%,

11/01/2028

(a)

518,000‌

523,985‌

2,384,998‌

Pharmaceuticals

.78

AdaptHealth

LLC

5.13%,

03/01/2030

(a)

2,064,000‌

1,800,089‌

BellRing

Brands,

Inc.

7.00%,

03/15/2030

(a)

1,581,000‌

1,628,575‌

Jazz

Securities

DAC

4.38%,

01/15/2029

(a)

2,273,000‌

2,117,385‌

Owens

Minor,

Inc.

4.50%,

03/31/2029

(a),(e)

955,000‌

874,479‌

6,420,528‌

Pipelines

.86

Midstream,

Inc.

4.13%,

06/15/2029

(a)

1,796,000‌

1,651,120‌

Genesis

Energy

LP/Genesis

Energy

Finance

Corp.

8.25%,

01/15/2029

1,607,000‌

1,649,740‌

Hess

Midstream

Operations

4.25%,

02/15/2030

(a)

2,208,000‌

2,028,948‌

NGL

Energy

Operating

LLC/NGL

Energy

Finance

Corp.

8.13%,

02/15/2029

(a)

350,000‌

358,464‌

8.38%,

02/15/2032

(a)

930,000‌

953,349‌

Venture

Global

LNG,

Inc.

8.38%,

06/01/2031

(a)

143,000‌

147,471‌

9.50%,

02/01/2029

(a)

1,365,000‌

1,471,283‌

8,260,375‌

REITs

.80

CBL

Associates

0.00%,

12/15/2026

(f),(g),(h)

6,000,000‌

—‌

HAT

Holdings

LLC/HAT

Holdings

LLC

3.38%,

06/15/2026

(a)

1,175,000‌

1,106,738‌

3.75%,

09/15/2030

(a)

550,000‌

461,944‌

8.00%,

06/15/2027

(a)

364,000‌

379,543‌

Ladder

Capital

Finance

Holdings

LLLP/Ladder

Capital

Finance

Corp.

4.75%,

06/15/2029

(a)

3,091,000‌

2,809,809‌

4,758,034‌

Retail

.28

Bath

Body

Works,

Inc.

5.25%,

02/01/2028

344,000‌

336,895‌

6.63%,

10/01/2030

(a)

567,000‌

579,190‌

6.75%,

07/01/2036

297,000‌

299,974‌

9.38%,

07/01/2025

(a)

30,000‌

31,302‌

Schedule

Investments

Principal

Active

High

Yield

ETF

March

31,

2024

(unaudited)

See

accompanying

notes.

BONDS

(continued)

Principal

Amount

Value

Retail

(continued)

Fertitta

Entertainment

LLC/Fertitta

Entertainment

Finance

Co.,

Inc.

4.63%,

01/15/2029

(a)

995,000‌

912,391‌

6.75%,

01/15/2030

(a)

731,000‌

656,374‌

LSF9

Atlantis

Holdings

LLC/Victra

Finance

Corp.

7.75%,

02/15/2026

(a)

2,062,000‌

2,043,414‌

Park

River

Holdings,

Inc.

5.63%,

02/01/2029

(a)

840,000‌

714,197‌

5,573,737‌

Software

.96

Cloud

Software

Group,

Inc.

6.50%,

03/31/2029

(a)

1,715,000‌

1,627,469‌

Telecommunications

.96

Frontier

Communications

Holdings

LLC

8.63%,

03/15/2031

(a)

1,305,000‌

1,332,834‌

Level

Financing,

Inc.

10.50%,

05/15/2030

(a)

295,000‌

301,638‌

1,634,472‌

Transportation

.98

Watco

Cos.

LLC/Watco

Finance

Corp.

6.50%,

06/15/2027

(a)

1,681,000‌

1,661,522‌

TOTAL

BONDS

147,960,853‌

SENIOR

FLOATING

RATE

INTERESTS

.63

Principal

Amount

Value

Airlines

.30

–

—

American

Airlines,

Inc.,

Series

2021

Term

Loan

(3-month

Term

Secured

Overnight

Financing

Rate

4.75%),

10.33%,

04/20/2028

1,151,750‌

1,194,780‌

United

Airlines,

Inc.,

Series

2024

Term

Loan

(3-month

Term

Secured

Overnight

Financing

Rate

2.75%),

8.08%,

02/15/2031

1,147,273‌

1,147,089‌

WestJet

Loyalty

LP,

Series

Term

Loan

(3-month

Term

Secured

Overnight

Financing

Rate

3.75%),

9.06%,

02/14/2031

1,560,000‌

1,558,705‌

3,900,574‌

Auto

Parts

Equipment

.13

Tenneco,

Inc.,

Series

2022

Term

Loan

(3-month

Term

Secured

Overnight

Financing

Rate

5.00%),

10.42%-10.45%,

11/17/2028

225,000‌

211,349‌

Food

.21

Fiesta

Purchaser,

Inc.,

Series

2024

Term

Loan

(3-month

Term

Secured

Overnight

Financing

Rate

4.00%),

9.32%,

02/12/2031

2,055,000‌

2,057,281‌

Forest

Products

Paper

.65

Spectrum

Group

Buyer,

Inc.,

Series

2022

Term

Loan

(3-month

Term

Secured

Overnight

Financing

Rate

6.50%),

11.81%,

05/19/2028

1,359,456‌

1,107,956‌

Healthcare

Services

.81

Star

Parent,

Inc.,

Series

Term

Loan

(3-month

Term

Secured

Overnight

Financing

Rate

4.00%),

9.31%,

09/27/2030

1,385,000‌

1,375,651‌

SENIOR

FLOATING

RATE

INTERESTS

(continued)

Principal

Amount

Value

Mining

.53

Arsenal

AIC

Parent

LLC

(1-month

Term

Secured

Overnight

Financing

Rate

4.50%),

9.83%,

08/18/2030

902,738‌

904,769‌

TOTAL

SENIOR

FLOATING

RATE

INTERESTS

9,557,580‌

U.S.

GOVERNMENT

AGENCY

OBLIGATIONS

.90

Principal

Amount

Value

U.S.

Treasury

.90

–

3.50%,

04/30/2028

1,583,200‌

1,535,766‌

TOTAL

U.S.

GOVERNMENT

AGENCY

OBLIGATIONS

1,535,766‌

INVESTMENT

COMPANIES

.25

Held

Value

Money

Market

Funds

.25

—

Principal

Government

Money

Market

Fund,

Class

R-6

5.22%

(i),(j),(k)

3,552,910‌

State

Street

Institutional

U.S.

Government

Money

Market

Fund,

Premier

Class

5.26%

(i)

10,471,192‌

TOTAL

INVESTMENT

COMPANIES

14,024,102‌

Total

Investments

173,078,301‌

Other

Assets

and

Liabilities

(1.85%)

(

3,145,350‌

)

TOTAL

NET

ASSETS

100.00%

169,932,951‌

(a)

Security

exempt

from

registration

under

Rule

144A

the

Securities

Act

1933.

These

securities

may

resold

transactions

exempt

from

registration,

normally

qualified

institutional

buyers.

the

end

the

period,

the

value

these

securities

totaled

$122,801,770

72.26%

net

assets.

(b)

Perpetual

security.

Perpetual

securities

pay

indefinite

stream

interest,

but

they

may

called

the

issuer

earlier

date.

Date

shown,

any,

reflects

the

call

date

final

legal

maturity

date.

Rate

shown

period

end.

(c)

Rate

shown

period

end.

The

rate

may

variable

floating

rate

fixed

rate

which

may

convert

variable

floating

rate

the

future.

(d)

Payment

kind;

the

issuer

has

the

option

paying

additional

securities

lieu

cash.

(e)

Security

portion

the

security

was

loan.

the

end

the

period,

the

value

these

securities

totaled

$3,490,041

2.05%

net

assets.

(f)

Security

defaulted.

(g)

Non-income

producing

security.

(h)

The

value

these

investments

was

determined

using

significant

unobservable

inputs,

good

faith

the

Advisor,

under

procedures

established

and

periodically

reviewed

the

Board

Trustees.

(i)

1-day

yield

shown

period

end.

(j)

Affiliated

Security.

Security

either

affiliate

(and

registered

under

the

Investment

Company

Act

1940)

affiliate

defined

the

Investment

Company

Act

1940

(controls

5.00%

the

outstanding

voting

the

security).

Please

see

Affiliated

Securities

sub-schedule

for

transactional

information.

(k)

Security

portion

the

security

was

received

collateral

for

securities

lending.

the

end

the

period,

the

value

these

securities

totaled

$3,552,910

2.09%

net

assets.

Portfolio

Summary

Sector

Percent

Consumer,

Cyclical

19.21%

Financial

16.77%

Consumer,

Non-cyclical

15.35%

Energy

11.44%

Industrial

8.73%

Basic

Materials

8.49%

Money

Market

Funds

8.25%

Communications

4.90%

Utilities

4.23%

Technology

3.58%

Government

0.90%

Other

Assets

and

Liabilities

(1.85)%

TOTAL

NET

ASSETS

100.00%

Schedule

Investments

Principal

Focused

Blue

Chip

ETF

March

31,

2024

(unaudited)

See

accompanying

notes.

COMMON

STOCKS

.92

Held

Value

Aerospace

Defense

.71

—

TransDigm

Group,

Inc.

1,456‌

1,793,210‌

Commercial

Services

.31

CoStar

Group,

Inc.

(a)

13,779‌

1,331,051‌

Moody's

Corp.

1,761‌

692,126‌

2,023,177‌

Distribution

Wholesale

.25

Copart,

Inc.

(a)

14,773‌

855,652‌

Diversified

Financial

Services

.90

Charles

Schwab

Corp.

12,260‌

886,888‌

Mastercard,

Inc.,

Class

5,702‌

2,745,912‌

Visa,

Inc.,

Class

5,956‌

1,662,201‌

5,295,001‌

Healthcare

Products

.43

Danaher

Corp.

6,765‌

1,689,356‌

Insurance

.70

Progressive

Corp.

8,667‌

1,792,509‌

Internet

.43

Alphabet,

Inc.,

Class

(a)

27,780‌

4,229,783‌

Amazon.com,

Inc.

(a)

25,000‌

4,509,500‌

Netflix,

Inc.

(a)

933‌

566,639‌

9,305,922‌

Lodging

.90

Hilton

Worldwide

Holdings,

Inc.

5,184‌

1,105,799‌

Pharmaceuticals

.42

Zoetis,

Inc.

3,205‌

542,318‌

Private

Equity

.60

Brookfield

Corp.,

Class

41,821‌

1,751,045‌

REITs

.82

American

Tower

Corp.

5,437‌

1,074,297‌

Retail

.27

O'Reilly

Automotive,

Inc.

(a)

766‌

864,722‌

COMMON

STOCKS

(continued)

Held

Value

Software

.34

Adobe,

Inc.

(a)

2,555‌

1,289,253‌

Intuit,

Inc.

2,060‌

1,339,000‌

Microsoft

Corp.

12,526‌

5,269,938‌

Roper

Technologies,

Inc.

1,776‌

996,052‌

8,894,243‌

Transportation

.84

Union

Pacific

Corp.

4,394‌

1,080,616‌

TOTAL

COMMON

STOCKS

38,067,867‌

INVESTMENT

COMPANIES

.01

Held

Value

Money

Market

Funds

.01

—

State

Street

Institutional

U.S.

Government

Money

Market

Fund,

Premier

Class

5.26%

(b)

5,611‌

TOTAL

INVESTMENT

COMPANIES

5,611‌

Total

Investments

38,073,478‌

Other

Assets

and

Liabilities

0.07%

25,219‌

TOTAL

NET

ASSETS

100.00%

38,098,697‌

(a)

Non-income

producing

security.

(b)

1-day

yield

shown

period

end.

Portfolio

Summary

Sector

Percent

Financial

26.02%

Communications

24.43%

Technology

23.34%

Consumer,

Non-cyclical

11.16%

Industrial

7.55%

Consumer,

Cyclical

7.42%

Money

Market

Funds

0.01%

Other

Assets

and

Liabilities

0.07%

TOTAL

NET

ASSETS

100.00%

Affiliated

Securities

June

30,

2023

Value

Purchases

Cost

Sales

Proceeds

March

31,

2024

Value

Principal

Government

Money

Market

Fund,

Class

R-6

5.22%

—‌

142,950‌

—‌

142,950‌

—‌

Income

(a)

Realized

Gain/(Loss)

Investments

Realized

Gain

from

Capital

Gain

Distributions

Change

Unrealized

Gain/(Loss)

Principal

Government

Money

Market

Fund,

Class

R-6

5.22%

—‌

(a)

Amount

excludes

earnings

from

securities

lending

collateral.

Schedule

Investments

Principal

Healthcare

Innovators

ETF

March

31,

2024

(unaudited)

See

accompanying

notes.

COMMON

STOCKS

.79

Held

Value

Biotechnology

.58

—

2seventy

bio,

Inc.

(a)

8,462‌

45,272‌

Molecular

Therapeutics,

Inc.

(a)

4,739‌

150,985‌

Aadi

Bioscience,

Inc.

(a)

5,352‌

12,524‌

ACADIA

Pharmaceuticals,

Inc.

(a)

18,537‌

342,749‌

Adicet

Bio,

Inc.

(a)

8,568‌

20,135‌

ADMA

Biologics,

Inc.

(a)

30,964‌

204,362‌

Aerovate

Therapeutics,

Inc.

(a)

3,989‌

117,955‌

Agenus,

Inc.

(a)

44,794‌

25,981‌

Akero

Therapeutics,

Inc.

(a)

5,494‌

138,778‌

Allogene

Therapeutics,

Inc.

(a)

19,685‌

87,992‌

Allovir,

Inc.

(a)

14,327‌

10,815‌

Alnylam

Pharmaceuticals,

Inc.

(a)

7,218‌

1,078,730‌

Amicus

Therapeutics,

Inc.

(a)

32,450‌

382,261‌

AnaptysBio,

Inc.

(a)

4,135‌

93,120‌

Anavex

Life

Sciences

Corp.

(a)

11,574‌

58,912‌

ANI

Pharmaceuticals,

Inc.

(a)

2,530‌

174,899‌

Apellis

Pharmaceuticals,

Inc.

(a)

12,457‌

732,222‌

Arbutus

Biopharma

Corp.

(a)

25,400‌

65,532‌

Arcellx,

Inc.

(a)

5,747‌

399,704‌

Arcturus

Therapeutics

Holdings,

Inc.

(a)

3,773‌

127,414‌

Arcus

Biosciences,

Inc.

(a)

9,072‌

171,279‌

Arcutis

Biotherapeutics,

Inc.

(a)

8,492‌

84,156‌

Arrowhead

Pharmaceuticals,

Inc.

(a)

12,354‌

353,324‌

Atara

Biotherapeutics,

Inc.

(a)

16,865‌

11,704‌

Atea

Pharmaceuticals,

Inc.

(a)

16,386‌

66,199‌

Aurinia

Pharmaceuticals,

Inc.

(a)

17,062‌

85,481‌

Avidity

Biosciences,

Inc.

(a)

9,136‌

233,151‌

Axsome

Therapeutics,

Inc.

(a)

4,982‌

397,564‌

Beam

Therapeutics,

Inc.

(a)

8,533‌

281,930‌

BioCryst

Pharmaceuticals,

Inc.

(a)

23,519‌

119,477‌

Biohaven

Ltd.

(a)

9,084‌

496,804‌

Bio-Rad

Laboratories,

Inc.,

Class

(a)

3,146‌

1,088,107‌

Bluebird

Bio,

Inc.

(a),(b)

17,159‌

21,964‌

Blueprint

Medicines

Corp.

(a)

6,906‌

655,103‌

Bridgebio

Pharma,

Inc.

(a)

19,301‌

596,787‌

Therapeutics,

Inc.

(a),(b)

13,238‌

108,155‌

Cara

Therapeutics,

Inc.

(a)

9,986‌

9,087‌

Caribou

Biosciences,

Inc.

(a)

12,418‌

63,829‌

Cassava

Sciences,

Inc.

(a),(b)

5,556‌

112,731‌

Celldex

Therapeutics,

Inc.

(a)

5,733‌

240,614‌

Cerevel

Therapeutics

Holdings,

Inc.

(a)

17,604‌

744,121‌

Chinook

Therapeutics,

Inc.

(a),(c)

9,493‌

3,797‌

Cogent

Biosciences,

Inc.

(a)

9,477‌

63,685‌

Crinetics

Pharmaceuticals,

Inc.

(a)

7,203‌

337,172‌

Cullinan

Oncology,

Inc.

(a)

6,456‌

110,010‌

Cytokinetics,

Inc.

(a)

10,792‌

756,627‌

Day

One

Biopharmaceuticals,

Inc.

(a)

9,741‌

160,921‌

Deciphera

Pharmaceuticals,

Inc.

(a)

9,858‌

155,066‌

Denali

Therapeutics,

Inc.

(a)

15,561‌

319,312‌

Design

Therapeutics,

Inc.

(a)

9,227‌

37,185‌

Dyne

Therapeutics,

Inc.

(a)

8,308‌

235,864‌

Edgewise

Therapeutics,

Inc.

(a)

10,183‌

185,738‌

Editas

Medicine,

Inc.

(a)

10,552‌

78,296‌

Emergent

BioSolutions,

Inc.

(a)

7,870‌

19,911‌

Erasca,

Inc.

(a)

25,478‌

52,485‌

Esperion

Therapeutics,

Inc.

(a)

29,151‌

78,125‌

Evolus,

Inc.

(a)

8,774‌

122,836‌

Fate

Therapeutics,

Inc.

(a)

14,375‌

105,513‌

FibroGen,

Inc.

(a)

11,293‌

26,539‌

Geron

Corp.

(a)

63,900‌

210,870‌

Gossamer

Bio,

Inc.

(a)

29,935‌

35,323‌

Ideaya

Biosciences,

Inc.

(a)

6,906‌

303,035‌

IGM

Biosciences,

Inc.

(a),(b)

5,265‌

50,807‌

Illumina,

Inc.

(a)

6,635‌

911,118‌

ImmunityBio,

Inc.

(a),(b)

56,126‌

301,397‌

Immunovant,

Inc.

(a)

15,532‌

501,839‌

Inhibrx,

Inc.

(a)

5,871‌

205,250‌

Inovio

Pharmaceuticals,

Inc.

(a)

4,938‌

68,539‌

Insmed,

Inc.

(a)

15,931‌

432,208‌

Intellia

Therapeutics,

Inc.

(a)

10,055‌

276,613‌

COMMON

STOCKS

(continued)

Held

Value

Biotechnology

(continued)

Intra-Cellular

Therapies,

Inc.

(a)

10,537‌

729,160‌

Ionis

Pharmaceuticals,

Inc.

(a)

15,890‌

688,832‌

Iovance

Biotherapeutics,

Inc.

(a)

28,431‌

421,347‌

Karyopharm

Therapeutics,

Inc.

(a)

17,929‌

27,073‌

Keros

Therapeutics,

Inc.

(a)

3,612‌

239,114‌

Kezar

Life

Sciences,

Inc.

(a)

14,867‌

13,404‌

Kiniksa

Pharmaceuticals

Ltd.,

Class

(a)

5,889‌

116,190‌

Kodiak

Sciences,

Inc.

(a)

10,735‌

56,466‌

Krystal

Biotech,

Inc.

(a)

3,053‌

543,220‌

Kymera

Therapeutics,

Inc.

(a)

6,617‌

266,003‌

Ligand

Pharmaceuticals,

Inc.

(a)

2,155‌

157,531‌

Liquidia

Corp.

(a)

10,675‌

157,456‌

MacroGenics,

Inc.

(a)

10,366‌

152,588‌

Mersana

Therapeutics,

Inc.

(a)

17,670‌

79,162‌

Mineralys

Therapeutics,

Inc.

(a)

6,002‌

77,486‌

Mural

Oncology

PLC

(a)

1,661‌

8,122‌

Myriad

Genetics,

Inc.

(a)

9,799‌

208,915‌

Nektar

Therapeutics

(a)

50,456‌

47,136‌

NGM

Biopharmaceuticals,

Inc.

(a)

15,170‌

24,120‌

Nkarta,

Inc.

(a)

10,734‌

116,035‌

Novavax,

Inc.

(a),(b)

11,877‌

56,772‌

Nurix

Therapeutics,

Inc.

(a)

7,517‌

110,500‌

Nuvalent,

Inc.,

Class

(a)

6,208‌

466,159‌

Phathom

Pharmaceuticals,

Inc.

(a)

6,953‌

73,841‌

Praxis

Precision

Medicines,

Inc.

(a)

1,970‌

120,209‌

Precigen,

Inc.

(a)

46,946‌

68,072‌

Prime

Medicine,

Inc.

(a)

12,314‌

86,198‌

Prothena

Corp.

PLC

(a)

6,064‌

150,205‌

PTC

Therapeutics,

Inc.

(a)

8,315‌

241,883‌

RAPT

Therapeutics,

Inc.

(a)

4,826‌

43,338‌

Recursion

Pharmaceuticals,

Inc.,

Class

(a),(b)

24,092‌

240,197‌

REGENXBIO,

Inc.

(a)

5,998‌

126,378‌

Relay

Therapeutics,

Inc.

(a)

14,959‌

124,160‌

Replimune

Group,

Inc.

(a)

7,347‌

60,025‌

REVOLUTION

Medicines,

Inc.

(a)

12,205‌

393,367‌

Rigel

Pharmaceuticals,

Inc.

(a)

39,688‌

58,738‌

Rocket

Pharmaceuticals,

Inc.

(a)

9,854‌

265,467‌

Sage

Therapeutics,

Inc.

(a)

6,896‌

129,231‌

Sana

Biotechnology,

Inc.

(a)

25,357‌

253,570‌

Sangamo

Therapeutics,

Inc.

(a)

35,597‌

23,857‌

Sarepta

Therapeutics,

Inc.

(a)

9,547‌

1,235,955‌

Scilex

Holding

Co.

(a)

10,078‌

16,024‌

Seer,

Inc.

(a)

11,819‌

22,456‌

SpringWorks

Therapeutics,

Inc.

(a)

7,738‌

380,864‌

Stoke

Therapeutics,

Inc.

(a)

7,250‌

97,875‌

Sutro

Biopharma,

Inc.

(a)

11,598‌

65,529‌

Syndax

Pharmaceuticals,

Inc.

(a)

8,505‌

202,419‌

Therapeutics,

Inc.

(a)

16,730‌

254,463‌

Theravance

Biopharma,

Inc.

(a),(b)

9,160‌

82,165‌

Travere

Therapeutics,

Inc.

(a)

8,996‌

69,359‌

Ultragenyx

Pharmaceutical,

Inc.

(a)

8,080‌

377,255‌

Ventyx

Biosciences,

Inc.

(a)

6,888‌

37,884‌

Vera

Therapeutics,

Inc.

(a)

8,499‌

366,477‌

Veracyte,

Inc.

(a)

8,802‌

195,052‌

Vericel

Corp.

(a)

5,885‌

306,138‌

Verve

Therapeutics,

Inc.

(a)

8,128‌

107,940‌

Vir

Biotechnology,

Inc.

(a)

15,192‌

153,895‌

Viridian

Therapeutics,

Inc.

(a)

5,445‌

95,342‌

Xencor,

Inc.

(a)

7,290‌

161,328‌

Zentalis

Pharmaceuticals,

Inc.

(a)

7,566‌

119,240‌

27,927,177‌

Chemicals

.10

Codexis,

Inc.

(a)

12,992‌

45,342‌

Healthcare

Products

.57

10X

Genomics,

Inc.,

Class

(a)

10,803‌

405,437‌

Adaptive

Biotechnologies

Corp.

(a)

18,281‌

58,682‌

Alphatec

Holdings,

Inc.

(a)

13,592‌

187,434‌

AngioDynamics,

Inc.

(a)

6,975‌

40,943‌

Artivion,

Inc.

(a)

6,071‌

128,462‌

AtriCure,

Inc.

(a)

5,574‌

169,561‌

Schedule

Investments

Principal

Healthcare

Innovators

ETF

March

31,

2024

(unaudited)

See

accompanying

notes.

COMMON

STOCKS

(continued)

Held

Value

Healthcare

Products

(continued)

Axogen,

Inc.

(a)

7,442‌

60,057‌

Axonics,

Inc.

(a)

5,743‌

396,095‌

Azenta,

Inc.

(a)

7,950‌

479,226‌

BioLife

Solutions,

Inc.

(a)

5,874‌

108,963‌

Bionano

Genomics,

Inc.

(a)

5,950‌

6,604‌

Butterfly

Network,

Inc.

(a),(b)

27,115‌

29,284‌

CareDx,

Inc.

(a)

8,739‌

92,546‌

Cerus

Corp.

(a)

28,590‌

54,035‌

Cutera,

Inc.

(a)

2,703‌

3,973‌

Exact

Sciences

Corp.

(a)

19,311‌

1,333,618‌

Glaukos

Corp.

(a)

5,616‌

529,533‌

ICU

Medical,

Inc.

(a)

2,694‌

289,120‌

Inari

Medical,

Inc.

(a)

6,151‌

295,125‌

Inogen,

Inc.

(a)

4,514‌

36,428‌

Inotiv,

Inc.

(a),(b)

7,469‌

81,711‌

Inspire

Medical

Systems,

Inc.

(a)

3,180‌

683,032‌

iRhythm

Technologies,

Inc.

(a)

3,397‌

394,052‌

MaxCyte,

Inc.

(a)

16,156‌

67,694‌

MiMedx

Group,

Inc.

(a)

19,157‌

147,509‌

Natera,

Inc.

(a)

12,505‌

1,143,707‌

Nevro

Corp.

(a)

4,571‌

66,005‌

Novocure

Ltd.

(a)

11,615‌

181,542‌

OmniAb,

Inc.

(a)

19,080‌

103,414‌

OmniAb,

Inc.,

Earnout

(a)

977‌

—‌

OmniAb,

Inc.,

Earnout

(a)

977‌

—‌

Orthofix

Medical,

Inc.

(a)

5,038‌

73,152‌

OrthoPediatrics

Corp.

(a)

2,978‌

86,838‌

Pacific

Biosciences

California,

Inc.

(a)

28,630‌

107,363‌

Paragon

28,

Inc.

(a)

10,476‌

129,379‌

PROCEPT

BioRobotics

Corp.

(a)

5,486‌

271,118‌

Pulmonx

Corp.

(a)

5,731‌

53,126‌

Quanterix

Corp.

(a)

5,998‌

141,313‌

Quantum-Si,

Inc.

(a),(b)

29,252‌

57,626‌

RxSight,

Inc.

(a)

5,073‌

261,665‌

SI-BONE,

Inc.

(a)

4,868‌

79,689‌

Silk

Road

Medical,

Inc.

(a)

4,561‌

83,558‌

Surmodics,

Inc.

(a)

2,596‌

76,167‌

Tactile

Systems

Technology,

Inc.

(a)

3,758‌

61,067‌

Tandem

Diabetes

Care,

Inc.

(a)

7,836‌

277,473‌

TransMedics

Group,

Inc.

(a)

3,715‌

274,687‌

Treace

Medical

Concepts,

Inc.

(a)

7,217‌

94,182‌

Twist

Bioscience

Corp.

(a)

7,957‌

273,005‌

Zimvie,

Inc.

(a)

5,925‌

97,703‌

10,072,903‌

Healthcare

Services

.21

Nano-X

Imaging

Ltd.

(a),(b)

9,581‌

93,606‌

Pharmaceuticals

.05

AbCellera

Biologics,

Inc.

(a),(b)

34,204‌

154,944‌

Aclaris

Therapeutics,

Inc.

(a)

8,922‌

11,063‌

Agios

Pharmaceuticals,

Inc.

(a)

7,034‌

205,674‌

Alector,

Inc.

(a)

12,786‌

76,972‌

Alkermes

PLC

(a)

18,350‌

496,734‌

Amneal

Pharmaceuticals,

Inc.

(a)

32,292‌

195,690‌

Amylyx

Pharmaceuticals,

Inc.

(a)

7,836‌

22,254‌

Anika

Therapeutics,

Inc.

(a)

2,482‌

63,043‌

Arvinas,

Inc.

(a)

6,582‌

271,705‌

Bioxcel

Therapeutics,

Inc.

(a)

3,777‌

10,651‌

Coherus

Biosciences,

Inc.

(a)

10,390‌

24,832‌

Collegium

Pharmaceutical,

Inc.

(a)

4,762‌

184,861‌

Elanco

Animal

Health,

Inc.

(a)

54,828‌

892,600‌

Enanta

Pharmaceuticals,

Inc.

(a)

2,938‌

51,297‌

COMMON

STOCKS

(continued)

Held

Value

Pharmaceuticals

(continued)

Fulcrum

Therapeutics,

Inc.

(a)

16,233‌

153,239‌

Heron

Therapeutics,

Inc.

(a)

22,233‌

61,585‌

KalVista

Pharmaceuticals,

Inc.

(a)

6,622‌

78,537‌

Kura

Oncology,

Inc.

(a)

9,668‌

206,218‌

Lyell

Immunopharma,

Inc.

(a)

37,936‌

84,597‌

Madrigal

Pharmaceuticals,

Inc.

(a)

2,013‌

537,552‌

MannKind

Corp.

(a)

34,089‌

154,423‌

Mirum

Pharmaceuticals,

Inc.

(a)

4,999‌

125,575‌

Morphic

Holding,

Inc.

(a)

4,786‌

168,467‌

Ocugen,

Inc.

(a),(b)

59,354‌

97,341‌

Ocular

Therapeutix,

Inc.

(a)

12,337‌

112,267‌

Perrigo

Co.

PLC

15,067‌

485,007‌

PMV

Pharmaceuticals,

Inc.

(a)

9,331‌

15,863‌

Protagonist

Therapeutics,

Inc.

(a)

7,074‌

204,651‌

Revance

Therapeutics,

Inc.

(a)

9,117‌

44,856‌

Senseonics

Holdings,

Inc.

(a)

92,985‌

49,384‌

Seres

Therapeutics,

Inc.

(a)

14,929‌

11,557‌

SIGA

Technologies,

Inc.

12,178‌

104,244‌

Vaxcyte,

Inc.

(a)

10,328‌

705,506‌

Xeris

Biopharma

Holdings,

Inc.

(a)

25,454‌

56,253‌

Y-mAbs

Therapeutics,

Inc.

(a)

9,130‌

148,454‌

6,267,896‌

Software

.03

Outset

Medical,

Inc.

(a)

5,920‌

13,142‌

Transportation

.25

CryoPort,

Inc.

(a)

6,307‌

111,634‌

TOTAL

COMMON

STOCKS

44,531,700‌

INVESTMENT

COMPANIES

.72

Held

Value

Money

Market

Funds

.72

—

Principal

Government

Money

Market

Fund,

Class

R-6

5.22%

(d),(e),(f)

1,121,063‌

State

Street

Institutional

U.S.

Government

Money

Market

Fund,

Premier

Class

5.26%

(d)

91,027‌

TOTAL

INVESTMENT

COMPANIES

1,212,090‌

Total

Investments

45,743,790‌

Other

Assets

and

Liabilities

(2.51%)

(

1,119,149‌

)

TOTAL

NET

ASSETS

100.00%

44,624,641‌

(a)

Non-income

producing

security.

(b)

Security

portion

the

security

was

loan.

the

end

the

period,

the

value

these

securities

totaled

$1,020,394

2.29%

net

assets.

(c)

The

value

these

investments

was

determined

using

significant

unobservable

inputs,

good

faith

the

Advisor,

under

procedures

established

and

periodically

reviewed

the

Board

Trustees.

(d)

1-day

yield

shown

period

end.

(e)

Affiliated

Security.

Security

either

affiliate

(and

registered

under

the

Investment

Company

Act

1940)

affiliate

defined

the

Investment

Company

Act

1940

(controls

5.00%

the

outstanding

voting

the

security).

Please

see

Affiliated

Securities

sub-schedule

for

transactional

information.

(f)

Security

portion

the

security

was

received

collateral

for

securities

lending.

the

end

the

period,

the

value

these

securities

totaled

$1,121,063

2.51%

net

assets.

Portfolio

Summary

Sector

Percent

Consumer,

Non-cyclical

99.41%

Money

Market

Funds

2.72%

Industrial

0.25%

Basic

Materials

0.10%

Technology

0.03%

Other

Assets

and

Liabilities

(2.51)%

TOTAL

NET

ASSETS

100.00%

Schedule

Investments

Principal

Investment

Grade

Corporate

Active

ETF

March

31,

2024

(unaudited)

See

accompanying

notes.

BONDS

.65

Principal

Amount

Value

Aerospace

Defense

.75

—

BAE

Systems

PLC

5.00%,

03/26/2027

(a)

340,000‌

339,309‌

Boeing

Co.

2.20%,

02/04/2026

500,000‌

468,099‌

3.25%,

02/01/2028

654,000‌

601,699‌

5.71%,

05/01/2040

571,000‌

546,528‌

L3Harris

Technologies,

Inc.

5.05%,

06/01/2029

150,000‌

149,521‌

Lockheed

Martin

Corp.

5.70%,

11/15/2054

284,000‌

302,668‌

RTX

Corp.

4.13%,

11/16/2028

1,088,000‌

1,052,404‌

6.10%,

03/15/2034

203,000‌

216,963‌

3,677,191‌

Agriculture

.46

BAT

Capital

Corp.

5.83%,

02/20/2031

200,000‌

201,716‌

6.00%,

02/20/2034

155,000‌

156,945‌

358,661‌

Airlines

.28

Delta

Air

Lines,

Inc./SkyMiles

Ltd.

4.75%,

10/20/2028

(a)

1,011,262‌

989,072‌

Auto

Manufacturers

.46

Cummins,

Inc.

5.45%,

02/20/2054

150,000‌

153,354‌

Ford

Motor

Credit

Co.

LLC

5.80%,

03/08/2029

375,000‌

376,492‌

Hyundai

Capital

America

5.25%,

01/08/2027

(a)

320,000‌

319,713‌

5.40%,

01/08/2031

(a)

254,000‌

255,009‌

6.50%,

01/16/2029

(a)

521,000‌

546,588‌

Toyota

Motor

Credit

Corp.

4.80%,

01/05/2034

258,000‌

253,815‌

1,904,971‌

Banks

.25

AIB

Group

PLC

(6-month

Secured

Overnight

Financing

Rate

1.91%),

5.87%,

03/28/2035

(a),(b)

425,000‌

426,191‌

Bank

America

Corp.

(6-month

Secured

Overnight

Financing

Rate

1.65%),

5.47%,

01/23/2035

(b)

2,677,000‌

2,694,449‌

Bank

New

York

Mellon

Corp.

Series

(6-month

Secured

Overnight

Financing

Rate

1.61%),

4.97%,

04/26/2034

(b)

714,000‌

700,900‌

BNP

Paribas

(6-month

Secured

Overnight

Financing

Rate

1.59%),

5.50%,

05/20/2030

(a),(b)

390,000‌

390,852‌

Citigroup,

Inc.

(6-month

Secured

Overnight

Financing

Rate

1.54%),

5.61%,

09/29/2026

(b)

1,223,000‌

1,224,949‌

Deutsche

Bank

(6-month

Secured

Overnight

Financing

Rate

1.59%),

5.71%,

02/08/2028

(b)

305,000‌

304,557‌

HSBC

Holdings

PLC

(6-month

Secured

Overnight

Financing

Rate

1.46%),

5.55%,

03/04/2030

(b)

420,000‌

422,510‌

JPMorgan

Chase

Co.

(6-month

Secured

Overnight

Financing

Rate

1.62%),

5.34%,

01/23/2035

(b)

177,000‌

177,692‌

BONDS

(continued)

Principal

Amount

Value

Banks

(continued)

JPMorgan

Chase

Co.

(continued)

(6-month

Secured

Overnight

Financing

Rate

1.81%),

6.25%,

10/23/2034

(b)

2,635,000‌

2,815,214‌

Mizuho

Financial

Group,

Inc.

(1-year

Treasury

Constant

Maturity

Rate

1.12%),

5.38%,

05/26/2030

(b)

250,000‌

251,136‌

Morgan

Stanley

(6-month

Secured

Overnight

Financing

Rate

1.73%),

5.47%,

01/18/2035

(b)

2,516,000‌

2,538,489‌

PNC

Financial

Services

Group,

Inc.

(6-month

Secured

Overnight

Financing

Rate

1.90%),

5.68%,

01/22/2035

(b)

846,000‌

853,706‌

(6-month

Secured

Overnight

Financing

Rate

2.28%),

6.88%,

10/20/2034

(b)

146,000‌

159,874‌

Royal

Bank

Canada

4.95%,

02/01/2029

248,000‌

248,593‌

Truist

Financial

Corp.

(6-month

Secured

Overnight

Financing

Rate

1.62%),

5.44%,

01/24/2030

(b)

152,000‌

151,823‌

(6-month

Secured

Overnight

Financing

Rate

1.92%),

5.71%,

01/24/2035

(b)

177,000‌

177,764‌

(6-month

Secured

Overnight

Financing

Rate

1.63%),

5.90%,

10/28/2026

(b)

340,000‌

341,687‌

(6-month

Secured

Overnight

Financing

Rate

2.45%),

7.16%,

10/30/2029

(b)

350,000‌

373,240‌

UBS

Group

(1-year

Treasury

Constant

Maturity

Rate

1.75%),

4.75%,

05/12/2028

(a),(b)

1,228,000‌

1,203,267‌

(1-year

Treasury

Constant

Maturity

Rate

1.77%),

5.70%,

02/08/2035

(a),(b)

205,000‌

206,037‌

Wells

Fargo

Co.

(6-month

Secured

Overnight

Financing

Rate

2.10%),

2.39%,

06/02/2028

(b)

1,722,000‌

1,576,154‌

17,239,084‌

Beverages

.70

Anheuser-Busch

InBev

Worldwide,

Inc.

3.50%,

06/01/2030

759,000‌

706,989‌

4.38%,

04/15/2038

822,000‌

763,933‌

Constellation

Brands,

Inc.

4.75%,

05/09/2032

632,000‌

617,409‌

2,088,331‌

Biotechnology

.85

Amgen,

Inc.

5.60%,

03/02/2043

648,000‌

659,291‌

Chemicals

.23

International

Flavors

Fragrances,

Inc.

1.83%,

10/15/2027

(a)

200,000‌

177,343‌

Commercial

Services

.10

CoStar

Group,

Inc.

2.80%,

07/15/2030

(a)

1,001,000‌

853,317‌

Computers

.72

Apple,

Inc.

3.95%,

08/08/2052

657,000‌

553,733‌

Diversified

Financial

Services

.43

AerCap

Ireland

Capital

DAC/AerCap

Global

Aviation

Trust

3.00%,

10/29/2028

501,000‌

453,315‌

Schedule

Investments

Principal

Investment

Grade

Corporate

Active

ETF

March

31,

2024

(unaudited)

See

accompanying

notes.

BONDS

(continued)

Principal

Amount

Value

Diversified

Financial

Services

(continued)

AerCap

Ireland

Capital

DAC/AerCap

Global

Aviation

Trust

(continued)

3.85%,

10/29/2041

790‌

626‌

Blackstone

Holdings

Finance

Co.

LLC

2.85%,

08/05/2051

(a)

562,342‌

352,164‌

Lseg

U.S.

Fin

Corp.

5.30%,

03/28/2034

(a)

300,000‌

301,892‌

1,107,997‌

Electric

.43

Alliant

Energy

Finance

LLC

5.95%,

03/30/2029

(a)

117,000‌

120,502‌

Commonwealth

Edison

Co.

4.00%,

03/01/2049

564,000‌

449,644‌

Consolidated

Edison

Co.

New

York,

Inc.

5.90%,

11/15/2053

126,000‌

134,475‌

Duke

Energy

Carolinas

LLC

3.75%,

06/01/2045

564,000‌

439,497‌

Duke

Energy

Florida

LLC

6.20%,

11/15/2053

162,000‌

178,603‌

Entergy

Louisiana

LLC

4.95%,

01/15/2045

564,000‌

519,779‌

FirstEnergy

Corp.

Series

5.10%,

07/15/2047

424,000‌

372,212‌

Florida

Power

Light

Co.

3.95%,

03/01/2048

424,000‌

347,562‌

Indianapolis

Power

Light

Co.

5.70%,

04/01/2054

(a)

205,000‌

205,543‌

ITC

Holdings

Corp.

3.65%,

06/15/2024

596,000‌

592,959‌

Kentucky

Utilities

Co.

4.38%,

10/01/2045

615,000‌

528,727‌

MidAmerican

Energy

Co.

4.40%,

10/15/2044

564,000‌

490,939‌

Monongahela

Power

Co.

3.55%,

05/15/2027

(a)

440,000‌

418,511‌

National

Rural

Utilities

Cooperative

Finance

Corp.

5.00%,

02/07/2031

265,000‌

263,111‌

Northern

States

Power

Co.

5.10%,

05/15/2053

307,000‌

295,764‌

NRG

Energy,

Inc.

2.00%,

12/02/2025

(a)

570,000‌

534,964‌

Pacific

Gas

Electric

Co.

2.95%,

03/01/2026

1,084,000‌

1,034,906‌

5.55%,

05/15/2029

375,000‌

378,274‌

7,305,972‌

Engineering

Construction

.24

CIMIC

Finance

USA

Pty.

Ltd.

7.00%,

03/25/2034

(a),(c)

180,000‌

184,824‌

Entertainment

.26

Warnermedia

Holdings,

Inc.

4.28%,

03/15/2032

1,090,000‌

973,630‌

Environmental

Control

.51

Waste

Connections,

Inc.

4.20%,

01/15/2033

793,000‌

745,355‌

Waste

Management,

Inc.

4.63%,

02/15/2030

424,000‌

421,990‌

1,167,345‌

Food

.91

JBS

USA

LUX

SA/JBS

USA

Food

Co./JBS

USA

Finance,

Inc.

4.38%,

02/02/2052

482,400‌

350,319‌

Mars,

Inc.

2.38%,

07/16/2040

(a)

503,000‌

350,618‌

Sysco

Corp.

3.15%,

12/14/2051

736‌

504‌

701,441‌

BONDS

(continued)

Principal

Amount

Value

Gas

.77

NiSource,

Inc.

0.95%,

08/15/2025

1,377,000‌

1,295,836‌

5.25%,

03/30/2028

78,000‌

78,536‌

1,374,372‌

Healthcare

Products

.31

Boston

Scientific

Corp.

2.65%,

06/01/2030

1,151,000‌

1,013,741‌

Healthcare

Services

.37

Centene

Corp.

2.45%,

07/15/2028

1,233,000‌

1,093,318‌

HCA,

Inc.

5.45%,

04/01/2031

275,000‌

276,434‌

6.00%,

04/01/2054

324,000‌

328,854‌

UnitedHealth

Group,

Inc.

2.75%,

05/15/2040

580,000‌

426,792‌

5.38%,

04/15/2054

255,000‌

259,348‌

5.88%,

02/15/2053

212,000‌

229,364‌

2,614,110‌

Insurance

.19

AIA

Group

Ltd.

5.38%,

04/05/2034

(a)

200,000‌

199,802‌

Aon

North

America,

Inc.

5.45%,

03/01/2034

175,000‌

177,020‌

5.75%,

03/01/2054

250,000‌

256,301‌

Arthur

Gallagher

Co.

2.40%,

11/09/2031

709,000‌

581,313‌

6.75%,

02/15/2054

637,000‌

723,208‌

Athene

Holding

Ltd.

6.25%,

04/01/2054

325,000‌

329,837‌

Chubb

INA

Holdings,

Inc.

3.35%,

05/03/2026

579,000‌

559,304‌

Corebridge

Financial,

Inc.

5.75%,

01/15/2034

450,000‌

459,084‌

Everest

Reinsurance

Holdings,

Inc.

3.13%,

10/15/2052

509,000‌

329,222‌

MetLife,

Inc.

5.00%,

07/15/2052

281,000‌

264,538‌

New

York

Life

Insurance

Co.

3.75%,

05/15/2050

(a)

440,000‌

338,247‌

SiriusPoint

Ltd.

7.00%,

04/05/2029

175,000‌

174,975‌

Swiss

Subordinated

Finance

PLC

(3-month

Term

Secured

Overnight

Financing

Rate

1.81%),

5.70%,

04/05/2035

(a),(b)

400,000‌

399,334‌

4,792,185‌

Internet

.00

Netflix,

Inc.

5.88%,

11/15/2028

747,000‌

776,527‌

Media

.32

Charter

Communications

Operating

LLC/Charter

Communications

Operating

Capital

4.80%,

03/01/2050

370,000‌

273,878‌

Comcast

Corp.

3.97%,

11/01/2047

652,000‌

524,077‌

Paramount

Global

4.20%,

05/19/2032

274,000‌

227,626‌

1,025,581‌

Mining

.87

Glencore

Funding

LLC

5.37%,

04/04/2029

(a)

875,000‌

876,735‌

6.13%,

10/06/2028

(a)

556,000‌

574,553‌

1,451,288‌

Oil

Gas

.94

Capital

Markets

America,

Inc.

4.70%,

04/10/2029

254,000‌

253,363‌

Marathon

Oil

Corp.

4.40%,

07/15/2027

500,000‌

485,871‌

5.70%,

04/01/2034

175,000‌

174,991‌

Schedule

Investments

Principal

Investment

Grade

Corporate

Active

ETF

March

31,

2024

(unaudited)

See

accompanying

notes.

BONDS

(continued)

Principal

Amount

Value

Oil

Gas

(continued)

Marathon

Oil

Corp.

(continued)

6.60%,

10/01/2037

255,000‌

268,281‌

Occidental

Petroleum

Corp.

6.60%,

03/15/2046

300,000‌

323,318‌

1,505,824‌

Packaging

Containers

.95

Packaging

Corp.

America

5.70%,

12/01/2033

521,000‌

538,097‌

Smurfit

Kappa

Treasury

ULC

5.20%,

01/15/2030

(a)

200,000‌

199,605‌

737,702‌

Pharmaceuticals

.90

AbbVie,

Inc.

3.20%,

11/21/2029

582,000‌

536,311‌

4.05%,

11/21/2039

862,000‌

767,524‌

4.95%,

03/15/2031

770,000‌

775,495‌

5.40%,

03/15/2054

115,000‌

118,369‌

Becton

Dickinson

Co.

3.70%,

06/06/2027

1,510,000‌

1,450,718‌

Bristol-Myers

Squibb

Co.

4.13%,

06/15/2039

424,000‌

375,723‌

Pfizer

Investment

Enterprises

Pte.

Ltd.

5.11%,

05/19/2043

295,000‌

288,467‌

Zoetis,

Inc.

3.90%,

08/20/2028

1,074,000‌

1,033,404‌

5,346,011‌

Pipelines

.39

Cheniere

Energy,

Inc.

5.65%,

04/15/2034

(a)

170,000‌

171,214‌

Energy

Transfer

3.75%,

05/15/2030

729,000‌

671,922‌

5.15%,

03/15/2045

497,000‌

451,591‌

5.95%,

05/15/2054

140,000‌

139,712‌

Enterprise

Products

Operating

LLC

3.13%,

07/31/2029

1,166,000‌

1,075,519‌

Kinder

Morgan,

Inc.

5.40%,

02/01/2034

600,000‌

597,593‌

MPLX

4.88%,

12/01/2024

571,000‌

567,907‌

Sabine

Pass

Liquefaction

LLC

5.00%,

03/15/2027

502,000‌

500,532‌

4,175,990‌

REITs

.73

Crown

Castle,

Inc.

5.80%,

03/01/2034

521,000‌

532,959‌

Invitation

Homes

Operating

Partnership

2.00%,

08/15/2031

428,000‌

340,085‌

Kimco

Realty

LLC

3.20%,

04/01/2032

798,000‌

687,655‌

Realty

Income

Corp.

3.10%,

12/15/2029

70‌

63‌

3.20%,

02/15/2031

624,000‌

553,075‌

2,113,837‌

Semiconductors

.10

Broadcom,

Inc.

4.11%,

09/15/2028

511,000‌

493,703‌

Intel

Corp.

5.00%,

02/21/2031

185,000‌

185,189‌

5.15%,

02/21/2034

175,000‌

175,399‌

BONDS

(continued)

Principal

Amount

Value

Semiconductors

(continued)

Marvell

Technology,

Inc.

5.95%,

09/15/2033

315,000‌

326,439‌

Micron

Technology,

Inc.

5.30%,

01/15/2031

193,000‌

194,116‌

6.75%,

11/01/2029

234,000‌

251,167‌

1,626,013‌

Software

.84

Fiserv,

Inc.

4.40%,

07/01/2049

469,000‌

397,895‌

Intuit,

Inc.

5.50%,

09/15/2053

244,000‌

253,288‌

Oracle

Corp.

2.80%,

04/01/2027

424,000‌

397,647‌

4.00%,

07/15/2046

424,000‌

334,014‌

6.15%,

11/09/2029

219,000‌

230,812‌

Take-Two

Interactive

Software,

Inc.

4.00%,

04/14/2032

654,000‌

604,103‌

4.95%,

03/28/2028

254,000‌

253,024‌

VMware

LLC

4.65%,

05/15/2027

1,299,000‌

1,276,942‌

3,747,725‌

Telecommunications

.09

AT&T,

Inc.

3.50%,

09/15/2053

1,741,000‌

1,228,314‌

T-Mobile

USA,

Inc.

3.38%,

04/15/2029

1,381,000‌

1,277,191‌

3.50%,

04/15/2031

500,000‌

451,539‌

6.00%,

06/15/2054

201,000‌

214,838‌

3,171,882‌

Transportation

.46

Norfolk

Southern

Corp.

5.35%,

08/01/2054

360,000‌

357,383‌

Water

.84

Essential

Utilities,

Inc.

2.40%,

05/01/2031

784,000‌

649,405‌

TOTAL

BONDS

76,421,779‌

INVESTMENT

COMPANIES

.34

Held

Value

Money

Market

Funds

.34

—

Principal

Government

Money

Market

Fund,

Class

R-6

5.22%

(d),(e),(f)

141,750‌

State

Street

Institutional

U.S.

Government

Money

Market

Fund,

Premier

Class

5.26%

(d)

899,401‌

TOTAL

INVESTMENT

COMPANIES

1,041,151‌

Total

Investments

77,462,930‌

Other

Assets

and

Liabilities

0.01%

6,877‌

TOTAL

NET

ASSETS

100.00%

77,469,807‌

(a)

Security

exempt

from

registration

under

Rule

144A

the

Securities

Act

1933.

These

securities

may

resold

transactions

exempt

from

registration,

normally

qualified

institutional

buyers.

the

end

the

period,

the

value

these

securities

totaled

$10,935,206

14.12%

net

assets.

(b)

Rate

shown

period

end.

The

rate

may

variable

floating

rate

fixed

rate

which

may

convert

variable

floating

rate

the

future.

(c)

Security

portion

the

security

was

loan.

the

end

the

period,

the

value

these

securities

totaled

$138,481

0.18%

net

assets.

(d)

1-day

yield

shown

period

end.

(e)

Affiliated

Security.

Security

either

affiliate

(and

registered

under

the

Investment

Company

Act

1940)

affiliate

defined

the

Investment

Company

Act

1940

(controls

5.00%

the

outstanding

voting

the

security).

Please

see

Affiliated

Securities

sub-schedule

for

transactional

information.

(f)

Security

portion

the

security

was

received

collateral

for

securities

lending.

the

end

the

period,

the

value

these

securities

totaled

$141,750

0.18%

net

assets.

Schedule

Investments

Principal

Investment

Grade

Corporate

Active

ETF

March

31,

2024

(unaudited)

See

accompanying

notes.

Portfolio

Summary

Sector

Percent

Financial

32.60%

Consumer,

Non-cyclical

17.60%

Utilities

12.04%

Industrial

7.91%

Technology

7.66%

Energy

7.33%

Communications

6.41%

Consumer,

Cyclical

5.00%

Basic

Materials

2.10%

Money

Market

Funds

1.34%

Other

Assets

and

Liabilities

0.01%

TOTAL

NET

ASSETS

100.00%

Affiliated

Securities

June

30,

2023

Value

Purchases

Cost

Sales

Proceeds

March

31,

2024

Value

Principal

Government

Money

Market

Fund,

Class

R-6

5.22%

384,880‌

7,213,745‌

7,456,875‌

141,750‌

384,880‌

7,213,745‌

7,456,875‌

141,750‌

Income

(a)

Realized

Gain/(Loss)

Investments

Realized

Gain

from

Capital

Gain

Distributions

Change

Unrealized

Gain/(Loss)

Principal

Government

Money

Market

Fund,

Class

R-6

5.22%

—‌

(a)

Amount

excludes

earnings

from

securities

lending

collateral.

Futures

Contracts

Description

and

Expiration

Date

Type

Contracts

Notional

Amount

Value

and

Unrealized

Appreciation/(Depreciation)

U.S.

Year

Note

CBT;

June

2024

Short

5‌

535,078‌

615‌

U.S.

Year

Note

CBT;

June

2024

Short

21‌

2,326,734‌

(

6,795‌

)

U.S.

Year

Ultra

Note

CBT;

June

2024

Short

24‌

2,750,625‌

1,794‌

U.S.

Long

Bond

CBT;

June

2024

Long

16‌

1,927,000‌

13,995‌

U.S.

Ultra

Bond

CBT;

June

2024

Long

17‌

2,193,000‌

16,458‌

Total

26,067‌

Schedule

Investments

Principal

Quality

ETF

March

31,

2024

(unaudited)

See

accompanying

notes.

COMMON

STOCKS

.76

Held

Value

Auto

Parts

Equipment

.08

—

Aptiv

PLC

(a)

6,609‌

526,407‌

Building

Materials

.41

Martin

Marietta

Materials,

Inc.

892‌

547,634‌

Trane

Technologies

PLC

1,923‌

577,285‌

Vulcan

Materials

Co.

1,969‌

537,379‌

1,662,298‌

Chemicals

.27

Ecolab,

Inc.

2,426‌

560,164‌

PPG

Industries,

Inc.

3,788‌

548,881‌

1,109,045‌

Commercial

Services

.53

Corpay,

Inc.

(a)

1,724‌

531,923‌

Gartner,

Inc.

(a)

1,129‌

538,160‌

Global

Payments,

Inc.

4,032‌

538,917‌

PayPal

Holdings,

Inc.

(a)

8,930‌

598,221‌

2,207,221‌

Computers

.25

Accenture

PLC,

Class

1,993‌

690,794‌

Apple,

Inc.

12,094‌

2,073,879‌

Hewlett

Packard

Enterprise

Co.

30,493‌

540,641‌

International

Business

Machines

Corp.

3,583‌

684,210‌

NetApp,

Inc.

4,982‌

522,960‌

4,512,484‌

Distribution

Wholesale

.27

Copart,

Inc.

(a)

9,630‌

557,769‌

Grainger,

Inc.

539‌

548,325‌

1,106,094‌

Diversified

Financial

Services

.04

Cboe

Global

Markets,

Inc.

2,766‌

508,197‌

Electrical

Components

Equipment

.10

AMETEK,

Inc.

2,936‌

536,994‌

Electronics

.29

Allegion

PLC

3,827‌

515,535‌

Jabil,

Inc.

4,090‌

547,856‌

Keysight

Technologies,

Inc.

(a)

3,443‌

538,416‌

1,601,807‌

Environmental

Control

.11

Republic

Services,

Inc.

2,836‌

542,924‌

Food

.09

Sysco

Corp.

6,567‌

533,109‌

Hand

Machine

Tools

.06

Snap-on,

Inc.

1,739‌

515,127‌

Healthcare

Products

.39

Agilent

Technologies,

Inc.

3,621‌

526,892‌

Boston

Scientific

Corp.

(a)

8,962‌

613,807‌

Edwards

Lifesciences

Corp.

(a)

5,939‌

567,531‌

Stryker

Corp.

1,756‌

628,420‌

Thermo

Fisher

Scientific,

Inc.

1,269‌

737,555‌

West

Pharmaceutical

Services,

Inc.

1,336‌

528,669‌

3,602,874‌

Healthcare

Services

.10

IQVIA

Holdings,

Inc.

(a)

2,128‌

538,150‌

Home

Builders

.34

Horton,

Inc.

3,541‌

582,672‌

PulteGroup,

Inc.

4,626‌

557,988‌

1,140,660‌

Household

Products

Wares

.19

Church

Dwight

Co.,

Inc.

4,933‌

514,561‌

Kimberly-Clark

Corp.

4,280‌

553,618‌

1,068,179‌

Insurance

.23

Berkshire

Hathaway,

Inc.,

Class

(a)

264‌

111,017‌

COMMON

STOCKS

(continued)

Held

Value

Internet

.15

Alphabet,

Inc.,

Class

(a)

1,494‌

225,490‌

Alphabet,

Inc.,

Class

(a)

5,543‌

843,977‌

Amazon.com,

Inc.

(a)

6,005‌

1,083,182‌

CDW

Corp.

2,130‌

544,811‌

F5,

Inc.

(a)

2,653‌

502,982‌

category

include

listed

equities

and

listed

derivatives.

Level

—

Other

significant

observable

inputs

(including

quoted

prices

for

similar

investments,

interest

rates,

prepayment

speeds,

credit

risk,

etc.).

Investments

which

are

generally

included

this

category

include

certain

corporate

bonds,

senior

floating

rate

interests,

OTC

derivatives,

mortgage-

backed

securities

and

municipal

bonds.

Level

—

Significant

unobservable

inputs

(including

the

Funds’

assumptions

determining

the

fair

value

investments).

Investments

which

are

generally

included

this

category

include

certain

corporate

bonds

and

certain

common

stocks.

Principal

Exchange-Traded

Funds

March

31,

2024

(unaudited)

The

availability

observable

inputs

can

vary

from

security

and

affected

wide

variety

factors,

including,

for

example,

the

type

security,

whether

the

security

new

and

not

yet

established

the

market

place,

and

other

characteristics

particular

the

transaction.

the

extent

that

valuation

based

models

inputs

that

are

less

observable

unobservable

the

market,

the

determination

fair

value

requires

judgment.

Accordingly,

the

degree

judgment

exercised

the

Funds

determining

fair

value

greatest

for

instruments

categorized

Level

certain

cases,

the

inputs

used

measure

fair

value

may

fall

into

different

levels

the

fair

value

hierarchy.

such

cases,

for

disclosure

purposes,

the

level

the

fair

value

hierarchy

within

which

the

fair

value

measurement

its

entirety

falls

determined

based

the

lowest

level

input

that

significant

the

fair

value

measurement

its

entirety.

Fair

value

market

based

measure

considered

from

the

perspective

market

participant

who

holds

the

asset

rather

than

entity

specific

measure.

Therefore,

even

when

market

assumptions

are

not

readily

available,

the

Funds’

own

assumptions

are

set

reflect

those

that

market

participants

would

use

pricing

the

asset

liability

the

measurement

date.

The

Funds

use

prices

and

inputs

that

are

current

the

measurement

date,

the

extent

available.

Investments

which

are

included

the

Level

category

may

valued

using

quoted

prices

from

brokers

and

dealers

participating

the

market

for

these

investments.

These

investments

are

classified

Level

investments

due

the

lack

market

transparency

and

market

corroboration

support

these

quoted

prices.

Valuation

models

may

used

the

pricing

source

for

other

investments

classified

Level

Valuation

models

rely

one

significant

unobservable

inputs

such

prepayment

rates,

probability

default,

loss

severity

the

event

default.

Significant

increases

any

those

inputs

isolation

would

result

significantly

lower

fair

value

measurement.

The

fair

values

these

entities

are

dependent

economic,

political

and

other

considerations.

The

values

the

underlying

investee

entities

may

affected

significant

changes

the

economic

conditions,

changes

government

policies,

and

other

factors

(e.g.,

natural

disasters,

pandemics,

accidents,

conflicts,

etc.).

The

inputs

methodology

used

for

valuing

securities

are

not

necessarily

indication

the

risk

associated

with

investing

those

instruments.

During

the

period

there

were

significant

purchases,

sales,

transfers

into

out

Level

The

following

summary

the

inputs

used

March

31,

2024,

valuing

the

Funds’

securities

carried

fair

value:

Fund

Level

Quoted

Prices

Level

Other

Significant

Observable

Inputs

Level

Significant

Unobservable

Inputs

Totals

(Level

1,2,3)

Principal

Active

High

Yield

ETF

Bonds

—

147,960,853

—

147,960,853

Senior

Floating

Rate

Interests

—

9,557,580

—

9,557,580

U.S.

Government

Agency

Obligations

—

1,535,766

—

1,535,766

Investment

Companies

14,024,102

—

14,024,102

Total

investments

securities

14,024,102

159,054,199

—

173,078,301

Principal

Focused

Blue

Chip

ETF

Common

Stocks

38,067,867

—

38,067,867

Investment

Companies

5,611

—

5,611

Total

investments

securities

38,073,478

—

38,073,478

Principal

Healthcare

Innovators

ETF

Common

Stocks

Basic

Materials

45,342

—

45,342

Consumer,

Non-cyclical

44,357,785

—

3,797

44,361,582

Industrial

111,634

—

111,634

Technology

13,142

—

13,142

Investment

Companies

1,212,090

—

1,212,090

Total

investments

securities

45,739,993

—

3,797

45,743,790

Principal

Investment

Grade

Corporate

Active

ETF

Bonds

—

76,421,779

—

76,421,779

Investment

Companies

1,041,151

—

1,041,151

Total

investments

securities

1,041,151

76,421,779

—

77,462,930

Fair

Valuation

(continued)

Principal

Exchange-Traded

Funds

March

31,

2024

(unaudited)

The

Funds’

Schedules

Investments

for

the

period

ended

March

31,

2024 has

not

been

audited.

This

report

provided

for

the

general

information

the

Funds’

shareholders.

For

information

regarding

the

Funds

and

their

holdings,

please

see

the

Funds’

prospectus.

Fund

Level

Quoted

Prices

Level

Other

Significant

Observable

Inputs

Level

Significant

Unobservable

Inputs

Totals

(Level

1,2,3)

Principal

Investment

Grade

Corporate

Active

ETF

(continued)

Derivatives

Assets

Interest

Rate

Contracts

Futures

32,862

—

32,862

Derivatives

Liabilities

Interest

Rate

Contracts

Futures

(

6,795

)

—

(

6,795

)

Principal

Quality

ETF

Common

Stocks

48,651,584

—

48,651,584

Investment

Companies

94,330

—

94,330

Total

investments

securities

48,745,914

—

48,745,914

Principal

Real

Estate

Active

Opportunities

ETF

Common

Stocks

9,272,699

—

9,272,699

Investment

Companies

115,696

—

115,696

Total

investments

securities

9,388,395

—

9,388,395

Principal

Spectrum

Preferred

Securities

Active

ETF

Bonds

—

838,793,745

—

838,793,745

Investment

Companies

5,886,783

—

5,886,783

Total

investments

securities

5,886,783

838,793,745

—

844,680,528

Principal

Spectrum

Tax-Advantaged

Dividend

Active

ETF

Preferred

Stocks

1,797,823

—

1,797,823

Bonds

—

21,786,532

—

21,786,532

Investment

Companies

280,874

—

280,874

Total

investments

securities

2,078,697

21,786,532

—

23,865,229

Principal

U.S.

Mega-Cap

ETF

Common

Stocks

2,268,060,123

—

2,268,060,123

Investment

Companies

5,662,432

—

5,662,432

Total

investments

securities

2,273,722,555

—

2,273,722,555

Principal

U.S.

Small-Cap

ETF

Common

Stocks

Basic

Materials

12,783,506

—

12,783,506

Communications

17,931,625

—

17,931,625

Consumer,

Cyclical

64,611,589

—

64,611,589

Consumer,

Non-cyclical

115,742,925

—

3,863

115,746,788

Energy

39,994,417

—

39,994,417

Financial

105,555,074

—

105,555,074

Government

370,546

—

370,546

Industrial

89,657,703

—

89,657,703

Technology

60,881,064

—

60,881,064

Utilities

13,269,488

—

13,269,488

Investment

Companies

3,020,938

—

3,020,938

Total

investments

securities

523,818,875

—

3,863

523,822,738

Principal

Value

ETF

Common

Stocks

60,223,401

—

60,223,401

Investment

Companies

195,970

—

195,970

Total

investments

securities

60,419,371

—

60,419,371

For

additional

detail

regarding

sector

and/or

sub-industry

classifications,

please

see

the

Schedules

Investments.

Fair

Valuation

(continued)