
								Weighted Average
Loan Type	Unpaid Principal Balance		Carrying Value		Loan Count	Floating Rate Loan %		Coupon(1)		Term (Years)(2)
December 31, 2021
Loans held-for-investment
Senior secured loans(3)	$	1,001,869,994	$	1,001,825,294	66	100.0	%	3.9	%	3.7
	$	1,001,869,994	$	1,001,825,294	66	100.0	%	3.9	%	3.7


								Weighted Average
Loan Type	Unpaid Principal Balance		Carrying Value		Loan Count	Floating Rate Loan %		Coupon(1)		Term (Years)(2)
December 31, 2020
Loans held-for-investment
Senior secured loans(3)	$	547,345,334	$	547,345,334	40	100.0	%	5.1	%	3.1
	$	547,345,334	$	547,345,334	40	100.0	%	5.1	%	3.1

(1) Weighted average coupon assumes applicable one-month LIBOR of 0.10% and 0.14% as of December 31, 2021 and December 31, 2020, respectively, inclusive of weighted average LIBOR floors of 0.49% and 1.64%, respectively.

(2) Weighted average term assumes all extension options are exercised by the borrower; provided, however, that our loans may be repaid prior to such date.

(3) As of December 31, 2021, $974,025,294 of the outstanding senior secured loans were held in VIEs and $27,800,000 of the outstanding senior secured loans were held outside of VIEs. As of December 31, 2020, $531,363,401 of the outstanding senior secured loans were held in VIEs and $15,981,933 of the outstanding senior secured loans were held outside of VIEs.

Activity: For the years ended December 31, 2021 and December 31, 2020, the loan portfolio activity was as follows:


	Commercial Mortgage Loans Held-for-Investment
Balance at December 31, 2019	$	635,260,420
Purchases and advances	57,601,572
Principal payments	(145,516,658)
Balance at December 31, 2020	$	547,345,334
Purchases and advances	983,694,326
Principal repayments	(528,802,705)
Accretion of purchase discount	46,088
Amortization of purchase premium	(457,749)
Balance at December 31, 2021	$	1,001,825,294

Loan Risk Ratings: As further described in Note 2, the Company evaluates the commercial mortgage loan portfolio on a quarterly basis and assigns a risk rating based on a variety of factors. The following table presents the principal balance and net book value of the loan portfolio based on the Company's internal risk ratings as of December 31, 2021 and December 31, 2020:


	December 31, 2021				December 31, 2020
Risk Rating	Number of Loans	Unpaid Principal Balance		Net Carrying Value	Number of Loans	Unpaid Principal Balance		Net Carrying Value
1	—	$	—	—	—	$	—	—
2	40	634,438,386		634,438,386	14	168,401,366		168,401,366
3	23	342,350,405		342,305,705	20	309,726,343		309,726,343
4	3	25,081,203		25,081,203	6	69,217,625		69,217,625
5	—	—		—	—	—		—
	66	1,001,869,994		1,001,825,294	40	547,345,334		547,345,334

As of December 31, 2021, the average risk rating of the commercial mortgage loan portfolio was 2.3 (Low Risk), weighted by investment carrying value, with 97.5% of commercial loans held-for-investment rated 3 (Moderate Risk) or better by the Company's Manager.

As of December 31, 2020, the average risk rating of the commercial mortgage loan portfolio was 3.1 (Moderate Risk), weighted by investment carrying value, with 84.4% of commercial loans held-for-investment rated 3 (Moderate Risk) or better by the Company's Manager.

The decrease in risk ratings is primarily the result of commercial mortgage loans that paid off with a risk rating of "2" of $133.6 million, a risk rating of "3" of $276.1 million and a risk rating of "4" of $17.8 million, offset by purchases of commercial mortgage loans with a risk rating of "2" of $599.0 million, a risk rating of "3" of $283.0 million and a risk rating of '4" of $0.1 million during the year ended December 31, 2021.

Concentration of Credit Risk: The following tables present the geographic and property types of collateral underlying the Company's commercial mortgage loans as a percentage of the loans' carrying value as of December 31, 2021 and December 31, 2020:


	December 31, 2021		December 31, 2020
Geography
South	46.2	%	36.5	%
Southwest	27.5		38.7
West	13.9		1.8
Mid-Atlantic	7.9		6.2
Midwest	4.5		16.8
Total	100.0	%	100.0	%


	December 31, 2021		December 31, 2020
Collateral Property Type
Multifamily	92.0	%	89.5	%
Self-Storage	5.2		0.8
Retail	1.7		6.4
Office	1.1		3.3
Total	100.0	%	100.0	%

We did not have any impaired loans, nonaccrual loans, or loans in maturity default as of December 31, 2021 or December 31, 2020.