In the normal course of business, our operations are exposed to market risks, including the effect of changes in foreign currency exchange rates and interest rates. We may enter into derivative financial instruments to offset these underlying market risks. There have been no significant changes in our policy or strategy from what was disclosed in our Annual Report on Form 10-K for the year ended December 31, 2020.

The following table presents the fair value of our derivative financial instruments recognized within Other Assets and Other Liabilities on the Consolidated Balance Sheets (in thousands):

	September 30, 2021				December 31, 2020
	Asset		Liability		Asset		Liability
Undesignated derivatives
Foreign currency contracts
Forwards
Brazilian real	$	495	$	21	$	620	$	66
British pound sterling		6,045		1,690		174		7,589
Canadian dollar		2,970		2,326		80		5,827
Chinese renminbi		-		410		-		717
Euro		31,144		-		73		6,247
Japanese yen		17,485		-		720		1,604
Swedish krona		1,578		397		-		2,355

Designated derivatives
Foreign currency contracts
Net investment hedges
British pound sterling		10,463		-		-		2,081
Canadian dollar		5,949		748		-		9,847

Interest rate swaps
Cash flow hedges
Euro		-		6		-		9
U.S. dollar		-		-		-		140
Total fair value of derivatives	$	76,129	$	5,598	$	1,667	$	36,482

The following table summarizes the activity of our undesignated foreign currency contracts for the nine months ended September 30 (in millions, except for weighted average forward rates and number of active contracts):

	2021																					2020
	CAD			EUR			GBP			JPY			SEK			Other			Total			CAD			EUR			GBP			JPY			SEK			Other			Total
Notional amounts at January 1 ($)		163			474			207			252			38			28			1,162			120			581			178			182			31			15			1,107
New contracts ($)		219			362			166			77			20			27			871			29			845			294			82			10			32			1,292
Matured, expired or settled contracts ($)		(199	)		(120	)		(115	)		(58	)		(14	)		(31	)		(537	)		(32	)		(1,099	)		(311	)		(66	)		(9	)		(31	)		(1,548	)
Notional amounts at September 30 ($)		183			716			258			271			44			24			1,496			117			327			161			198			32			16			851

Weighted average forward rate at September 30		1.26			1.23			1.37			103.19			8.47									1.34			1.17			1.31			102.80			9.35
Active contracts at September 30		73			87			69			78			71									48			55			47			48			31

The following table summarizes the undesignated derivative financial instruments exercised and associated realized and unrealized gains (losses) in Foreign Currency and Derivative Gains (Losses), Net in the Consolidated Statements of Income (in millions, except for number of exercised contracts):

Changes in the fair value of derivatives that are designated as net investment hedges of our foreign operations and cash flow hedges are recorded in Accumulated Other Comprehensive Income (Loss) (“AOCI/L”) and reflected within the Other Comprehensive Income (Loss) table below.

The following table summarizes the activity of our foreign currency contracts designated as net investment hedges for the nine months ended September 30 (in millions, except for weighted average forward rates and number of active contracts):

	2021								2020
	CAD			GBP		Total			CAD			GBP			Total
Notional amounts at January 1 ($)		377			135		512			97			387			484
New contracts ($)		535			300		835			298			324			622
Matured, expired or settled contracts ($)		(299	)		-		(299	)		(48	)		(576	)		(624	)
Notional amounts at September 30 ($)		613			435		1,048			347			135			482

Weighted average forward rate at September 30		1.26			1.38					1.32			1.35
Active contracts at September 30		7			4					6			1

The following table summarizes the activity of our interest rate swaps designated as cash flow hedges for the nine months ended September 30 (in millions):

	2021								2020
	EUR ⁽¹⁾		USD ⁽¹⁾			Total			EUR		USD			Total
Notional amounts at January 1 ($)		165		250			415			-		-			-
New contracts ($)		-		-			-			165		1,500			1,665
Matured, expired or settled contracts ($)		-		(250	)		(250	)		-		(1,250	)		(1,250	)
Notional amounts at September 30 ($)		165		-			165			165		250			415

The following table summarizes our debt and accrued interest, designated as a hedge of our net investment in international subsidiaries as of the quarter ended (in millions):

The following table summarizes the unrealized gains (losses) in Foreign Currency and Derivative Gains (Losses), Net on the remeasurement of the unhedged portion of our debt and accrued interest, including euro and British pound sterling denominated debt, for the three and nine months ended September 30 (in millions):

The change in Other Comprehensive Income (Loss) in the Consolidated Statements of Comprehensive Income during the periods presented was due to the translation into U.S. dollars from the consolidation of the financial statements of our consolidated subsidiaries whose functional currency is not the U.S. dollar. The change in fair value of the effective portion of our derivative financial instruments that have been designated as net investment hedges and cash flow hedges and the translation of the hedged portion of our debt, as discussed above, are also included in Other Comprehensive Income (Loss).

The following table presents these changes in Other Comprehensive Income (Loss) (in thousands):

	Three Months Ended September 30,					Nine Months Ended September 30,
	2021		2020			2021			2020
Derivative net investment hedges	$	25,549	$	(4,234	)	$	11,090		$	18,290
Debt designated as nonderivative net investment hedges		15,118		(46,570	)		(3,715	)		2,439
Cumulative translation adjustment		8,041		5,228			194,506			(200,891	)
Total foreign currency translation gains (losses), net	$	48,708	$	(45,576	)	$	201,881		$	(180,162	)

Cash flow hedges^{(1) (2)}	$	872	$	1,581		$	8,246		$	(12,857	)
Our share of derivatives from unconsolidated co-investment ventures		2,876		798			5,133			(6,839	)
Total unrealized gains (losses) on derivative contracts, net	$	3,748	$	2,379		$	13,379		$	(19,696	)
Total change in other comprehensive income (loss)	$	52,456	$	(43,197	)	$	215,260		$	(199,858	)

There have been no significant changes in our policy from what was disclosed in our Annual Report on Form 10-K for the year ended December 31, 2020.

At September 30, 2021 and December 31, 2020, other than the derivatives discussed previously, we had no significant financial assets or financial liabilities that were measured at fair value on a recurring basis in the Consolidated Financial Statements. All of our derivatives held at September 30, 2021 and December 31, 2020, were classified as Level 2 of the fair value hierarchy.

Acquired properties and assets we expect to sell or contribute are significant nonfinancial assets that met the criteria to be measured at fair value on a nonrecurring basis. At September 30, 2021 and December 31, 2020, we estimated the fair value of our properties using Level 2 or Level 3 inputs from the fair value hierarchy. See more information on our acquired properties in Notes 2 and 3 and assets held for sale or contribution in Note 5.

At September 30, 2021 and December 31, 2020, the carrying amounts of certain financial instruments, including cash and cash equivalents, accounts and notes receivable, accounts payable and accrued expenses were representative of their fair values.

The differences in the fair value of our debt from the carrying value in the table below were the result of differences in interest rates or borrowing spreads that were available to us at September 30, 2021 and December 31, 2020, as compared with those in effect when the debt was issued or assumed, including reduced borrowing spreads due to our improved credit ratings. The fair value of the senior notes decreased during the nine months ended September 30, 2021 due to the increase in bond yields in the market as compared to the weighted average interest rates on our senior notes. The senior notes and many of the issuances of secured mortgage debt contain prepayment penalties or yield maintenance provisions that could make the cost of refinancing the debt at lower rates exceed the benefit that would be derived from doing so. We evaluate this on an on-going basis and have taken the opportunity to refinance some of our debt at lower rates and longer maturities as discussed in Note 6.

The following table reflects the carrying amounts and estimated fair values of our debt (in thousands):

	September 30, 2021				December 31, 2020
	Carrying Value		Fair Value		Carrying Value		Fair Value
Credit Facilities	$	100,000	$	100,000	$	171,794	$	171,794
Senior notes		14,887,589		15,239,275		14,275,870		15,452,381
Term loans and unsecured other		1,405,981		1,417,333		1,764,311		1,785,706
Secured mortgage		742,098		766,439		637,101		673,549
Total	$	17,135,668	$	17,523,047	$	16,849,076	$	18,083,430