(1)	Weighted average effective interest rate as of December 31, 2021.

(2)	Includes variable rate mortgages payable with interest rate cap agreements.

(3)	Includes variable rate mortgages payable with interest rates fixed by interest rate swap agreements.

(4)	As of December 31, 2021, excludes $6.4 million of net deferred financing costs related to unfunded mortgage loans that were included in "Other assets, net."

As of December 31, 2021 and 2020, the net carrying value of real estate collateralizing our mortgages payable totaled $1.8 billion. Our mortgages payable contain covenants that limit our ability to incur additional indebtedness on these properties and, in certain circumstances, require lender approval of tenant leases and/or yield maintenance upon repayment prior to maturity. Certain mortgages payable are recourse to us. See Note 19 for additional information. We were not in default under any mortgage loan as of December 31, 2021.

During the year ended December 31, 2021, we entered into two separate mortgage loans with an aggregate principal balance of $190.0 million, collateralized by 1225 S. Clark Street and 1215 S. Clark Street. During the year ended December 31, 2020, we entered into four separate mortgage loans with an aggregate principal balance of $560.0 million, collateralized by 4747 Bethesda Avenue, The Bartlett, 1221 Van Street and 220 20th Street, and refinanced the mortgage payable collateralized by RTC-West, increasing the principal balance by $20.2 million. In December 2020, we repaid the mortgage payable collateralized by WestEnd25 with a principal balance of $94.7 million.

As of December 31, 2021 and 2020, we had various interest rate swap and cap agreements on certain of our mortgages payable with an aggregate notional value of $1.3 billion. See Note 17 for additional information.

Credit Facility

As of December 31, 2021 and 2020, our $1.4 billion credit facility consisted of a $1.0 billion revolving credit facility maturing in January 2025, a $200.0 million unsecured term loan ("Tranche A-1 Term Loan") maturing in January 2023 and a $200.0 million unsecured term loan ("Tranche A-2 Term Loan") maturing in July 2024.

Based on the terms as of December 31, 2021, the interest rate for the credit facility varies based on a ratio of our total outstanding indebtedness to a valuation of certain real property and assets, and ranges (i) in the case of the revolving credit facility from LIBOR plus 1.05% to LIBOR plus 1.50%, (ii) in the case of the Tranche A-1 Term Loan, from LIBOR plus 1.20% to LIBOR plus 1.70% and (iii) in the case of the Tranche A-2 Term Loan, from LIBOR plus 1.15% to LIBOR plus 1.70%. There are various LIBOR options in the credit facility, and we elected the one-month LIBOR option as of December 31, 2021. We were not in default under our credit facility as of December 31, 2021. Effective as of January 14,

2022, the Tranche A-1 Term Loan was amended to extend the maturity date to January 2025 with two one-year extension options, and to amend the interest rate to Secured Overnight Financing Rate ("SOFR") plus 1.05% to SOFR plus 1.65%, in each case including a credit spread adjustment. In connection with the loan amendment, we amended the related LIBOR-based interest rate swaps, extending the maturity to July 2024 and converting the hedged rate from one-month LIBOR to one-month SOFR.

The following is a summary of amounts outstanding under the credit facility:


	Effective	December 31,
	Interest Rate ⁽¹⁾	2021		2020

		(In thousands)
Revolving credit facility ^{(2) (3) (4)}	1.15%	$	300,000	$	—

Tranche A-1 Term Loan ⁽⁵⁾	2.59%	$	200,000	$	200,000
Tranche A-2 Term Loan ⁽⁵⁾	2.49%		200,000		200,000
Unsecured term loans			400,000		400,000
Unamortized deferred financing costs, net			(1,336)		(2,021)
Unsecured term loans, net		$	398,664	$	397,979

(1)	Effective interest rate as of December 31, 2021.

(2)	As of December 31, 2021 and 2020, letters of credit with an aggregate face amount of $911,000 and $1.5 million were outstanding under our revolving credit facility.

(3)	As of December 31, 2021 and 2020, excludes net deferred financing costs related to our revolving credit facility of $5.0 million and $6.7 million that were included in "Other assets, net."

(4)	The interest rate for the revolving credit facility excludes a 0.15% facility fee.

(5)

As of December 31, 2021 and 2020, the outstanding balance was fixed by interest rate swap agreements. As of December 31, 2021, the interest rate swaps mature concurrently with the respective term loan and fix LIBOR at a weighted average interest rate of 1.39% for the Tranche A-1 Term Loan and 1.34% for the Tranche A-2 Term Loan.

Principal Maturities

The following is a summary of principal maturities of debt outstanding, including mortgages payable, revolving credit facility and the term loans, as of December 31, 2021:


Year ending December 31,	Amount
	(In thousands)
2022	$	112,516
2023		373,344
2024		322,571
2025		858,890
2026		113,845
Thereafter		707,093
Total	$	2,488,259