Fair Value

Financial assets and liabilities measured at fair value on a recurring basis at September 30, 2015 and December 31, 2014 were (in millions):



2015	Level 1		Level 2		Level 3		Total
Assets:
Cash and cash equivalents	$	1,427.5					$	1,427.5
Short-term investments	2.5						2.5
Available-for-sale securities	5.0						5.0
Interest rate and foreign currency derivative instruments			$	92.1			92.1
Liabilities:
Interest rate and foreign currency derivative instruments			$	16.3			$	16.3
Contingent purchase price obligations					$	327.7	327.7



2014
Assets:
Cash and cash equivalents	$	2,388.1					$	2,388.1
Short-term investments	2.2						2.2
Available-for-sale securities	4.9						4.9
Interest rate and foreign currency derivative instruments			$	43.1			43.1
Liabilities:
Foreign currency derivative instruments			$	0.4			$	0.4
Contingent purchase price obligations					$	300.7	300.7

The changes in Level 3 contingent purchase price obligations for the nine months ended September 30, 2015 and 2014 were (in millions):



	2015			2014
January 1	$	300.7		$	220.2
Acquisitions	68.2			103.1
Revaluation and interest	26.3			0.1
Payments	(55.6		)	(74.5		)
Foreign currency translation	(11.9		)	(7.9		)
September 30	$	327.7		$	241.0

The carrying amount and fair value of our financial instruments at September 30, 2015 and December 31, 2014 were (in millions):



	2015				2014
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Assets:
Cash and cash equivalents	$	1,427.5	$	1,427.5	$	2,388.1	$	2,388.1
Short-term investments	2.5		2.5		2.2		2.2
Available-for-sale securities	5.0		5.0		4.9		4.9
Interest rate and foreign currency derivative instruments	92.1		92.1		43.1		43.1
Cost method investments	21.6		21.6		21.8		21.8
Liabilities:
Short-term borrowings	$	9.7	$	9.7	$	7.2	$	7.2
Interest rate and foreign currency derivative instruments	16.3		16.3		0.4		0.4
Contingent purchase price obligations	327.7		327.7		300.7		300.7
Debt	4,605.6		4,692.3		4,563.0		4,754.9

The estimated fair value of the foreign currency and interest rate derivative instruments is determined using model-derived valuations, taking into consideration foreign currency rates for the foreign currency derivatives and readily observable inputs for LIBOR interest rates and yield curves to derive the present value of the future cash flows for the interest rate swap derivatives and counterparty credit risk for each. The estimated fair value of the contingent purchase price obligations is calculated in accordance with the terms of each acquisition agreement and is discounted. The fair value of debt is based on quoted market prices.