			March 31,		December 31,
(in millions)			2013		2012
Fair Value Method		$	4,939	$	4,493
Equity Method:
	The Weather Channel		474		471
	Other		714		693
			1,188		1,164
Cost Method:
	AirTouch		1,541		1,538
	Other		606		594
			2,147		2,132
Total investments			8,274		7,789
Less: Current investments			2,841		1,464
Noncurrent investments		$	5,433	$	6,325

Investment Income (Loss), Net
		Three Months Ended
		March 31
(in millions)		2013		2012
Gains on sales and exchanges of investments, net		$	35	$	7
Investment impairment losses			(9)		(12)
Unrealized gains (losses) on securities underlying prepaid forward sale agreements			605		516
Mark to market adjustments on derivative component of prepaid forward sale
	agreements and indexed debt instruments		(602)		(470)
Interest and dividend income			30		29
Other, net			13		22
Investment income (loss), net		$	72	$	92

As of March 31, 2013, substantially all of our fair value method investments were equity securities held as collateral that were related to our obligations under prepaid forward sale agreements.

Prepaid Forward Sale Agreements
		March 31,		December 31,
(in millions)		2013		2012
Assets:
	Fair value equity securities held	$	4,540	$	4,143

Liabilities:
	Obligations under prepaid forward sale agreements	$	1,125	$	1,248
	Derivative component of prepaid forward sale agreements		2,888		2,302
Total liabilities		$	4,013	$	3,550

As of March 31, 2013, our prepaid forward sale obligations had an estimated fair value of $4.1 billion. The estimated fair values are based on Level 2 inputs using pricing models whose inputs are derived primarily from or corroborated by observable market data through correlation or other means for substantially the full term of the financial instrument.

We hold two series of preferred stock of AirTouch Communications, Inc. (“AirTouch”), a subsidiary of Vodafone, which are redeemable in April 2020. As of March 31, 2013, the estimated fair values of the AirTouch preferred stock and the associated liability related to redeemable preferred shares issued by one of our consolidated subsidiaries were $1.8 billion. The estimated fair value is based on Level 2 inputs using pricing models whose inputs are derived primarily from or corroborated by observable market data through correlation or other means for substantially the full term of the financial instrument.