Summary of Significant Accounting Policies (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2022

Dec. 31, 2021

Accounting Policies [Abstract]

Schedule of allowance for credit loss

The rollforward of the allowance for doubtful accounts and credit memo reserves for the three months ended March 31, 2022 is as follows:

Balance as of December 31, 2021	$	62,009
Credit memos charged to revenue	12,352
Allowance for bad debts charged to expense	6,699
Deductions and other(1)	(19,893)
Balance as of March 31, 2022	$	61,167

(1)Primarily consists of the issuance of credit memos, the write-off of accounts receivable, allowances associated with businesses acquired and the impact associated with currency translation adjustments.

Schedule of operating and financing lease right-of-use assets and lease liabilities

Operating and financing lease right-of-use assets and lease liabilities as of March 31, 2022 and December 31, 2021 are as follows:

DESCRIPTION	MARCH 31, 2022		DECEMBER 31, 2021
Assets:
Operating lease right-of-use assets	$	2,343,627	$	2,314,422
Financing lease right-of-use assets, net of accumulated depreciation(1)	284,468		298,049
Liabilities:
Current
Operating lease liabilities	$	265,186	$	259,957
Financing lease liabilities(1)	39,397		41,168
Long-term
Operating lease liabilities	$	2,196,846	$	2,171,472
Financing lease liabilities(1)	301,603		315,561

(1)Financing lease right-of-use assets, current financing lease liabilities and long-term financing lease liabilities are included within Property, Plant and Equipment, Net, Current portion of long-term debt and Long-term Debt, net of current portion, respectively, within our Condensed Consolidated Balance Sheets.

Operating and financing lease right-of-use assets and lease liabilities as of December 31, 2021 and 2020 are as follows:

	DECEMBER 31,
DESCRIPTION	2021		2020
Assets:
Operating lease right-of-use assets(1)	$	2,314,422	$	2,196,502
Financing lease right-of-use assets, net of accumulated depreciation(2)(3)	298,049		310,534
Liabilities:
Current
Operating lease liabilities	$	259,597	$	250,239
Financing lease liabilities(3)	41,168		43,149
Long-term
Operating lease liabilities	$	2,171,472	$	2,044,598
Financing lease liabilities(3)	315,561		323,162

(1)At December 31, 2021 and 2020, these assets are comprised of approximately 99% real estate related assets (which include land, buildings and racking) and 1% non-real estate related assets (which include warehouse equipment, vehicles, furniture and fixtures and computer hardware and software).

(2)At December 31, 2021, these assets are comprised of approximately 69% real estate related assets and 31% non-real estate related assets. At December 31, 2020, these assets are comprised of approximately 72% real estate related assets and 28% non-real estate related assets.

(3)Financing lease right-of-use assets, current financing lease liabilities and long-term financing lease liabilities are included within Property, Plant and Equipment, Net, Current portion of long-term debt and Long-term Debt, net of current portion, respectively, within our Consolidated Balance Sheets.

Schedule of lease terms and discount rates/Other lease information

The components of the lease expense for the three months ended March 31, 2022 and 2021 are as follows:

	THREE MONTHS ENDED MARCH 31,
DESCRIPTION	2022		2021
Operating lease cost(1)	$	143,530	$	132,675
Financing lease cost:
Depreciation of financing lease right-of-use assets	$	11,454	$	12,648
Interest expense for financing lease liabilities	4,678		4,975

(1)Operating lease cost, the majority of which is included in Cost of sales, includes variable lease costs of $30,508 and $28,368 for the three months ended March 31, 2022 and 2021, respectively.

Supplemental cash flow information relating to our leases for the three months ended March 31, 2022 and 2021 is as follows:

	THREE MONTHS ENDED MARCH 31,
CASH PAID FOR AMOUNTS INCLUDED IN MEASUREMENT OF LEASE LIABILITIES:	2022		2021
Operating cash flows used in operating leases	$	101,605	$	93,645
Operating cash flows used in financing leases (interest)	4,678		4,975
Financing cash flows used in financing leases	10,362		12,441
NON-CASH ITEMS:
Operating lease modifications and reassessments	$	23,767	$	31,994
New operating leases (including acquisitions and sale-leaseback transactions)	125,902		48,200

The components of the lease expense for the years ended December 31, 2021, 2020 and 2019 are as follows:

	YEAR ENDED DECEMBER 31,
DESCRIPTION	2021		2020		2019
Operating lease cost(1)	$	545,097	$	499,464	$	459,619
Financing lease cost:
Depreciation of financing lease right-of-use assets	$	50,970	$	51,629	$	59,258
Interest expense for financing lease liabilities	19,808		19,942		21,031

(1)Operating lease cost, the majority of which is included in Cost of sales, includes variable lease costs of $111,949, $111,501 and $105,922 for the years ended December 31, 2021, 2020 and 2019, respectively.

Weighted average remaining lease terms and discount rates as of December 31, 2021 and 2020 are as follows:

	DECEMBER 31, 2021				DECEMBER 31, 2020
	OPERATING LEASES		FINANCING LEASES		OPERATING LEASES		FINANCING LEASES
Remaining Lease Term	10.9 years		10.9 years		11.1 years		11.5 years
Discount Rate	6.6	%	5.9	%	6.9	%	5.9	%

Supplemental cash flow information relating to our leases for the years ended December 31, 2021, 2020 and 2019 is as follows:

	YEAR ENDED DECEMBER 31,
CASH PAID FOR AMOUNTS INCLUDED IN MEASUREMENT OF LEASE LIABILITIES:	2021		2020		2019
Operating cash flows used in operating leases	$	392,987	$	360,088	$	338,059
Operating cash flows used in financing leases (interest)	19,808		19,942		21,031
Financing cash flows used in financing leases	46,118		47,829		58,033
NON-CASH ITEMS:
Operating lease modifications and reassessments	$	144,310	$	143,382	$	108,023
New operating leases (including acquisitions and sale-leaseback transactions)	282,490		370,011		170,464

Schedule of changes in the carrying value of goodwill attributable to each reportable operating segment

The changes in the carrying value of goodwill attributable to each reportable operating segment for the three months ended March 31, 2022, as restated for the changes described above, are as follows:

	GLOBAL RIM BUSINESS		GLOBAL DATA CENTER BUSINESS		CORPORATE AND OTHER BUSINESS		TOTAL CONSOLIDATED
Goodwill balance, net of accumulated amortization as of December 31, 2021	$	3,972,852	$	426,074	$	64,605	$	4,463,531
Non-tax deductible goodwill acquired during the period	978		—		580,150		581,128
Fair value and other adjustments(1)	(16,993)		—		—		(16,993)
Currency effects	(1,004)		(2,702)		(269)		(3,975)
Goodwill balance, net accumulated amortization as of March 31, 2022	$	3,955,833	$	423,372	$	644,486	$	5,023,691
Accumulated goodwill impairment balance as of March 31, 2022	$	132,409	$	—	$	26,011	$	158,420

(1) This amount represents an adjustment to goodwill as a result of the deconsolidation of certain businesses, as described in Note 2.k.

The changes in the carrying value of goodwill attributable to each reportable operating segment for the years ended December 31, 2021 and 2020, as restated for the changes described above, are as follows:

	GLOBAL RIM BUSINESS		GLOBAL DATA CENTER BUSINESS		CORPORATE AND OTHER BUSINESS		TOTAL CONSOLIDATED
Goodwill balance, net of accumulated amortization, as of December 31, 2019	$	3,940,303	$	424,568	$	120,338	$	4,485,209
Non-tax deductible goodwill acquired during the year	54,258		—		—		54,258
Goodwill impairment	—		—		(23,000)		(23,000)
Fair value and other adjustments	(3,815)		—		403		(3,412)
Currency effects	31,895		12,419		240		44,554
Goodwill balance, net of accumulated amortization, as of December 31, 2020	4,022,641		436,987		97,981		4,557,609
Non-tax deductible goodwill acquired during the year	14,406		—		13,141		27,547
Goodwill allocated to IPM Divestment	—		—		(46,105)		(46,105)
Fair value and other adjustments	(6,091)		—		(1,268)		(7,359)
Currency effects	(58,104)		(10,913)		856		(68,161)
Goodwill balance, net of accumulated amortization, as of December 31, 2021	$	3,972,852	$	426,074	$	64,605	$	4,463,531
Accumulated Goodwill Impairment Balance as of December 31, 2020	$	132,409	$	—	$	26,011	$	158,420
Accumulated Goodwill Impairment Balance as of December 31, 2021	$	132,409	$	—	$	26,011	$	158,420

Assets and liabilities carried at fair value measured on a recurring basis

The assets and liabilities carried at fair value measured on a recurring basis as of March 31, 2022 and December 31, 2021 are as follows:

			FAIR VALUE MEASUREMENTS AT MARCH 31, 2022 USING
DESCRIPTION	TOTAL CARRYING VALUE AT MARCH 31, 2022		QUOTED PRICES IN ACTIVE MARKETS (LEVEL 1)		SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)		SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)
Money Market Funds	$	28,718	$	—	$	28,718	$	—
Time Deposits	3,167		—		3,167		—
Trading Securities	10,442		10,355		87		—
Derivative Assets	19,443		—		19,443		—
Deferred Purchase Obligation (as defined in Note 3)	275,100		—		—		275,100

			FAIR VALUE MEASUREMENTS AT DECEMBER 31, 2021 USING
DESCRIPTION	TOTAL CARRYING VALUE AT DECEMBER 31, 2021		QUOTED PRICES IN ACTIVE MARKETS (LEVEL 1)		SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)		SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)
Money Market Funds	$	101,022	$	—	$	101,022	$	—
Time Deposits	2,238		—		2,238		—
Trading Securities	11,147		11,062		85		—
Derivative Assets	11,021		—		11,021		—
Derivative Liabilities	8,344		—		8,344		—

The assets and liabilities carried at fair value and measured on a recurring basis as of December 31, 2021 and 2020, respectively, are as follows:

			FAIR VALUE MEASUREMENTS AT DECEMBER 31, 2021 USING
DESCRIPTION	TOTAL CARRYING VALUE AT DECEMBER 31, 2021		QUOTED PRICES IN ACTIVE MARKETS (LEVEL 1)			SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)			SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)
Money Market Funds(1)	$	101,022	$	—		$	101,022		$	—
Time Deposits(1)	2,238		—			2,238			—
Trading Securities	11,147		11,062		(2)	85		(3)	—
Derivative Assets(4)	11,021		—			11,021			—
Derivative Liabilities(4)	8,344		—			8,344			—

			FAIR VALUE MEASUREMENTS AT DECEMBER 31, 2020 USING
DESCRIPTION	TOTAL CARRYING VALUE AT DECEMBER 31, 2020		QUOTED PRICES IN ACTIVE MARKETS (LEVEL 1)			SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)			SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)
Money Market Funds(1)	$	62,657	$	—		$	62,657		$	—
Time Deposits(1)	2,121					2,121			—
Trading Securities	10,892		10,636		(2)	256		(3)	—
Derivative Liabilities(4)	49,703		—			49,703			—

(1)Money market funds and time deposits are measured based on quoted prices for similar assets and/or subsequent transactions.

(2)Certain trading securities are measured at fair value using quoted market prices.

(3)Certain trading securities are measured based on inputs other than quoted market prices that are observable.

(4)Derivative assets and liabilities include (i) interest rate swap agreements, including forward-starting interest rate swap agreements, to limit our exposure to changes in interest rates on a portion of our floating rate indebtedness and (ii) cross-currency swap agreements to hedge the variability of exchange rates impacts between the United States dollar and the Euro and certain of our Euro denominated subsidiaries. Our derivative financial instruments are measured using industry standard valuation models using market-based observable inputs, including interest rate curves, forward and spot prices for currencies and implied volatilities. Credit risk is also factored into the determination of the fair value of our derivative financial instruments. See Note 6 for additional information on our derivative financial instruments.

Schedule of changes in accumulated other comprehensive items, net

The changes in accumulated other comprehensive items, net for the three months ended March 31, 2022 and 2021 are as follows:

	THREE MONTHS ENDED MARCH 31, 2022						THREE MONTHS ENDED MARCH 31, 2021
	FOREIGN CURRENCY TRANSLATION AND OTHER ADJUSTMENTS		CHANGE IN FAIR VALUE OF DERIVATIVE INSTRUMENTS		TOTAL		FOREIGN CURRENCY TRANSLATION AND OTHER ADJUSTMENTS		CHANGE IN FAIR VALUE OF DERIVATIVE INSTRUMENTS		TOTAL
Beginning of Period	$	(341,024)	$	2,677	$	(338,347)	$	(206,190)	$	(49,703)	$	(255,893)
Other comprehensive (loss) income):
Foreign currency translation and other adjustments	27,223		—		27,223		(66,224)		—		(66,224)
Change in fair value of derivative instruments	—		16,766		16,766		—		15,206		15,206
Total other comprehensive (loss) income	27,223		16,766		43,989		(66,224)		15,206		(51,018)
End of Period	$	(313,801)	$	19,443	$	(294,358)	$	(272,414)	$	(34,497)	$	(306,911)

The changes in accumulated other comprehensive items, net for the years ended December 31, 2021, 2020 and 2019 are as follows:

	FOREIGN CURRENCY  TRANSLATION AND OTHER ADJUSTMENTS		CHANGE IN FAIR VALUE OF DERIVATIVE INSTRUMENTS		TOTAL
Balance as of December 31, 2018	$	(264,691)	$	(973)	$	(265,664)
Other comprehensive income (loss):
Foreign currency translation and other adjustments	11,866		—		11,866
Change in fair value of derivative instruments	—		(8,783)		(8,783)
Total other comprehensive income (loss)	11,866		(8,783)		3,083
Balance as of December 31, 2019	(252,825)		(9,756)		(262,581)
Other comprehensive income (loss):
Foreign currency translation and other adjustments	46,635		—		46,635
Change in fair value of derivative instruments	—		(39,947)		(39,947)
Total other comprehensive income (loss)	46,635		(39,947)		6,688
Balance as of December 31, 2020	(206,190)		(49,703)		(255,893)
Other comprehensive (loss) income:
Foreign currency translation and other adjustments	(134,834)		—		(134,834)
Change in fair value of derivative instruments	—		52,380		52,380
Total other comprehensive (loss) income	(134,834)		52,380		(82,454)
Balance as of December 31, 2021	$	(341,024)	$	2,677	$	(338,347)

Schedule of Contract Fulfillment Costs and related amortization

Contract Fulfillment Costs as of March 31, 2022 and December 31, 2021 are as follows:

	MARCH 31, 2022						DECEMBER 31, 2021
	GROSS CARRYING AMOUNT		ACCUMULATED AMORTIZATION		NET CARRYING AMOUNT		GROSS CARRYING AMOUNT		ACCUMULATED AMORTIZATION		NET CARRYING AMOUNT
Intake Costs asset	$	71,731	$	(45,432)	$	26,299	$	71,336	$	(42,678)	$	28,658
Commissions asset	121,501		(54,356)		67,145		114,791		(50,553)		64,238

During the years ended December 31, 2021, 2020 and 2019, capitalized interest is as follows:

	YEAR ENDED DECEMBER 31,
	2021		2020		2019
Capitalized interest	$	12,673	$	14,321	$	15,980

During the years ended December 31, 2021, 2020 and 2019, capitalized costs associated with the development of internal use computer software projects are as follows:

	YEAR ENDED DECEMBER 31,
	2021		2020		2019
Capitalized costs associated with the development of internal use computer software projects	$	48,557	$	38,329	$	34,650

Contract Fulfillment Costs, which are included as a component of Other within Other Assets, Net, as of December 31, 2021 and 2020 are as follows:

	DECEMBER 31, 2021						DECEMBER 31, 2020
DESCRIPTION	GROSS CARRYING AMOUNT		ACCUMULATED AMORTIZATION		NET CARRYING AMOUNT		GROSS CARRYING AMOUNT		ACCUMULATED AMORTIZATION		NET CARRYING AMOUNT
Intake Costs asset	$	71,336	$	(42,678)	$	28,658	$	63,721	$	(33,352)	$	30,369
Commissions asset	114,791		(50,553)		64,238		91,069		(38,787)		52,282

Amortization expense associated with the Intake Costs and Commissions assets for the years ended December 31, 2021, 2020 and 2019 are as follows:

	YEAR ENDED DECEMBER 31,
DESCRIPTION	2021		2020		2019
Intake Costs asset	$	17,530	$	13,300	$	10,144
Commissions asset	30,739		24,052		19,109

Schedule of deferred revenue liabilities

Deferred revenue liabilities are reflected in our Condensed Consolidated Balance Sheets as follows:

DESCRIPTION	LOCATION IN BALANCE SHEET	MARCH 31, 2022		DECEMBER 31, 2021
Deferred revenue - Current	Deferred revenue	$	301,965	$	307,470
Deferred revenue - Long-term	Other Long-term Liabilities	31,532		33,691

Deferred revenue liabilities are reflected as follows in our Consolidated Balance Sheets:

		DECEMBER 31,
DESCRIPTION	LOCATION IN BALANCE SHEET	2021		2020
Deferred revenue - Current	Deferred revenue	$	307,470	$	295,785
Deferred revenue - Long-term	Other Long-term Liabilities	33,691		35,612

Schedule of revenue

Storage rental revenue, including revenue associated with power and connectivity, associated with our Global Data Center Business for the three months ended March 31, 2022 and 2021 are as follows:

	THREE MONTHS ENDED MARCH 31,
	2022		2021
Storage rental revenue(1)	$	87,451	$	67,157

(1)Revenue associated with power and connectivity included within storage rental revenue was $28,318 and $13,133 for the three months ended March 31, 2022 and 2021, respectively.

Storage rental revenue, including revenue associated with power and connectivity, associated with our Global Data Center Business for the years ended December 31, 2021, 2020 and 2019 are as follows:

	YEAR ENDED DECEMBER 31,
	2021		2020		2019
Storage rental revenue(1)	$	289,592	$	263,695	$	246,925

(1)Revenue associated with power and connectivity included within storage rental revenue was $62,185, $47,451 and $43,269 for the years ended December 31, 2021, 2020 and 2019, respectively.

Schedule of stock-based compensation expense

Stock-based compensation expense for the Employee Stock-Based Awards for the three months ended March 31, 2022 and 2021 is as follows:

	THREE MONTHS ENDED MARCH 31,
	2022		2021
Stock-based compensation expense	$	11,341	$	10,953

Stock-based compensation expense for Employee Stock-Based Awards included in the accompanying Consolidated Statements of Operations for the years ended December 31, 2021, 2020 and 2019 is as follows:

	YEAR ENDED DECEMBER 31,
	2021		2020		2019
Stock-based compensation expense	$	61,001	$	37,674	$	35,654
Stock-based compensation expense, after tax	59,243		36,584		33,103

Schedule of fair value of RSU and earned PUs vested

The fair value of RSUs and earned PUs that vested during the three months ended March 31, 2022 and 2021 is as follows:

	THREE MONTHS ENDED MARCH 31,
	2022		2021
Fair value of RSUs vested	$	18,415	$	19,861
Fair value of earned PUs that vested	4,346		5,591

Other expense (income), net

Consolidated other expense (income), net for the three months ended March 31, 2022 and 2021 consists of the following:

	THREE MONTHS ENDED MARCH 31,
DESCRIPTION	2022		2021
Foreign currency transaction (gains) losses, net	$	(13,201)	$	2,314
Debt extinguishment expense	671		—
Other, net(1)	68,431		2,399
Other Expense (Income), Net	$	55,901	$	4,713

(1)On March 24, 2022, as a result of our loss of control, we deconsolidated the businesses included in the acquisition of OSG Records Management (Europe) Limited, excluding Ukraine. We recognized a loss of approximately $105,800 associated with the deconsolidation to Other expense (income), net in the first quarter of 2022 representing the difference between the net asset value prior to the deconsolidation and subsequent remeasurement of the retained investment to fair value of zero. We have concluded that the deconsolidation does not meet the criteria to be reported as discontinued operations in our consolidated financial statements, as it does not represent a strategic shift that will have a major effect on our operations and financial results. The loss was partially offset by a gain of approximately $35,800 associated with the Clutter Transaction (as defined in Note 4).

Consolidated other (income) expense, net for the years ended December 31, 2021, 2020 and 2019 consists of the following:

	YEAR ENDED DECEMBER 31,
	2021		2020		2019
Foreign currency transaction (gains) losses, net(1)	$	(15,753)	$	29,830	$	24,852
Debt extinguishment expense	—		68,300		—
Other, net(2)	(177,051)		45,415		9,046
Other (Income) Expense, Net	$	(192,804)	$	143,545	$	33,898

(1)The gain or loss on foreign currency transactions, calculated as the difference between the historical exchange rate and the exchange rate at the applicable measurement date, includes gains or losses primarily related to (i) borrowings in certain foreign currencies under our Revolving Credit Facility (as defined in Note 7), (ii) our previously outstanding 3% Euro Senior Notes due 2025 ("Euro Notes"), (iii) certain foreign currency denominated intercompany obligations of our foreign subsidiaries to us and between our foreign subsidiaries, which are not considered permanently invested and (iv) amounts that are paid or received on the net settlement amount from forward contracts (as more fully discussed in Note 6).

(2)Other, net for the year ended December 31, 2021 consists primarily of (a) a gain of approximately $179,000 associated with our IPM Divestment and (b) a gain of approximately $20,300 associated with the loss of control and related deconsolidation, as of May 18, 2021, of one of our wholly owned Netherlands subsidiaries, for which we had value-added tax liability exposure that was recorded in 2019, partially offset by (c) losses on our equity method investments. Other, net for the year ended December 31, 2020 consists primarily of (a) changes in the estimated value of our mandatorily redeemable noncontrolling interests and (b) losses on our equity method investments.

Provision (benefit) for income taxes

Our effective tax rates for the three months ended March 31, 2022 and 2021 are as follows:

	THREE MONTHS ENDED MARCH 31,
	2022(1)		2021(2)
Effective Tax Rate	19.5	%	23.9	%

(1)The primary reconciling items between the federal statutory tax rate of 21.0% and our overall effective tax rate for the three months ended March 31, 2022 were the benefits derived from the dividends paid deduction, the differences in the tax rates to which our foreign earnings are subject, and a release of valuation allowances on deferred tax assets of our U.S. taxable REIT subsidiaries (“TRS”) of approximately $9,900 as a result of the ITRenew Transaction.

(2)The primary reconciling items between the federal statutory tax rate of 21.0% and our overall effective tax rate for the three months ended March 31, 2021 were the benefits derived from the dividends paid deduction and the impacts of differences in the tax rates to which our foreign earnings are subject.

The provision (benefit) for income taxes for the years ended December 31, 2021, 2020 and 2019 consist of the following components:

	YEAR ENDED DECEMBER 31,
	2021		2020		2019
Federal—current	$	54,867	$	(10,424)	$	7,262
Federal—deferred	14,322		8,834		(3,356)
State—current	9,566		2,956		3,943
State—deferred	(526)		(625)		(1,126)
Foreign—current	83,154		50,063		49,350
Foreign—deferred	14,907		(21,195)		3,858
Provision (Benefit) for Income Taxes	$	176,290	$	29,609	$	59,931

Calculation of basic and diluted net income (loss) per share attributable to the entity

The calculation of basic and diluted income (loss) per share for the three months ended March 31, 2022 and 2021 are as follows:

	THREE MONTHS ENDED MARCH 31,
	2022		2021
Net Income (Loss)	$	41,707	$	46,631
Less: Net (Loss) Income Attributable to Noncontrolling Interests	(592)		1,028
Net Income (Loss) Attributable to Iron Mountain Incorporated (utilized in numerator of Earnings Per Share calculation)	$	42,299	$	45,603
Weighted-average shares—basic	290,328,000		288,756,000
Effect of dilutive potential stock options	995,625		56,437
Effect of dilutive potential RSUs and PUs	521,977		715,850
Weighted-average shares—diluted	291,845,602		289,528,287
Net Income (Loss) Per Share Attributable to Iron Mountain Incorporated:
Basic	$	0.15	$	0.16
Diluted	$	0.14	$	0.16
Antidilutive stock options, RSUs and PUs, excluded from the calculation	755,580		4,708,068

The calculation of basic and diluted income (loss) per share for the years ended December 31, 2021, 2020 and 2019 is as follows:

	YEAR ENDED DECEMBER 31,
	2021		2020		2019
Income (loss) from continuing operations	$	452,725	$	343,096	$	268,211
Less: Net income (loss) attributable to noncontrolling interests	2,506		403		938
Income (loss) from continuing operations (utilized in numerator of Earnings Per Share calculation)	450,219		342,693		267,273
Income (loss) from discontinued operations, net of tax	—		—		104
Net income (loss) attributable to Iron Mountain Incorporated	$	450,219	$	342,693	$	267,377
Weighted-average shares—basic	289,457,000		288,183,000		286,971,000
Effect of dilutive potential stock options	645,886		24,903		145,509
Effect of dilutive potential RSUs and PUs	872,204		435,287		570,435
Weighted-average shares—diluted	290,975,090		288,643,190		287,686,944
Earnings (losses) per share—basic:
Income (loss) from continuing operations	$	1.56	$	1.19	$	0.93
(Loss) income from discontinued operations, net of tax	—		—		—
Net income (loss) attributable to Iron Mountain Incorporated(1)	$	1.56	$	1.19	$	0.93
Earnings (losses) per share—diluted:
Income (loss) from continuing operations	$	1.55	$	1.19	$	0.93
(Loss) income from discontinued operations, net of tax	—		—		—
Net income (loss) attributable to Iron Mountain Incorporated(1)	$	1.55	$	1.19	$	0.93
Antidilutive stock options, RSUs and PUs, excluded from the calculation	1,447,722		5,663,981		4,475,745

(1)Columns may not foot due to rounding.