The Company holds short-term and long-term investments, which consist primarily of marketable debt and equity securities.

Information regarding the Company's short-term and long-term investments at October 28, 2011 is as follows:

			Unrealized		Unrealized
(in millions)	Cost		Gains		Losses		Fair Value
Available-for-sale securities:
Corporate debt securities	$	2,512	$	24	$	(13)	$	2,523
Auction rate securities		167		-		(40)		127
Mortgage-backed securities		933		10		(12)		931
U.S. government and agency securities		2,842		45		(2)		2,885
Foreign government and agency securities		90		1		-		91
Certificates of deposit		97		-		-		97
Other asset-backed securities		437		2		(1)		438
Marketable equity securities		79		111		(26)		164
Trading securities:
Exchange-traded funds		45		1		(2)		44
Cost method, equity method, and other investments		831		-		-		831
Total short-term and long-term investments	$	8,033	$	194	$	(96)	$	8,131

Information regarding the Company's short-term and long-term investments at April 29, 2011 is as follows:

			Unrealized		Unrealized
(in millions)	Cost		Gains		Losses		Fair Value
Available-for-sale securities:
Corporate debt securities	$	1,947	$	20	$	(6)	$	1,961
Auction rate securities		167		-		(34)		133
Mortgage-backed securities		783		10		(8)		785
U.S. government and agency securities		2,731		26		(1)		2,756
Foreign government and agency securities		130		1		-		131
Certificates of deposit		119		-		-		119
Other asset-backed securities		351		1		(3)		349
Marketable equity securities		73		164		-		237
Trading securities:
Exchange-traded funds		33		6		-		39
Cost method, equity method, and other investments		656		-		-		656
Total short-term and long-term investments	$	6,990	$	228	$	(52)	$	7,166

Information regarding the Company's available-for-sale and trading securities at October 28, 2011 and April 29, 2011 is as follows:

	October 28, 2011				April 29, 2011
(in millions)	Short-term		Long-term		Short-term		Long-term
Available-for-sale securities	$	1,118	$	6,138	$	1,046	$	5,425
Trading securities		-		44		-		39
Total	$	1,118	$	6,182	$	1,046	$	5,464

The following tables show the gross unrealized losses and fair values of the Company's available-for-sale securities that have been in a continuous unrealized loss position deemed to be temporary for less than 12 months and for more than 12 months, aggregated by investment category as of October 28, 2011 and April 29, 2011:

	October 28, 2011
		Less than 12 months			More than 12 months
			Unrealized				Unrealized
(in millions)	Fair Value		Losses		Fair Value		Losses
Corporate debt securities	$	793	$	(10)	$	10	$	(3)
Auction rate securities		-		-		127		(40)
Mortgage-backed securities		308		(3)		62		(9)
U.S. government and agency securities		679		(2)		-		-
Other asset-backed securities		-		-		16		(1)
Marketable equity securities		53		(26)		-		-
Total	$	1,833	$	(41)	$	215	$	(53)

	April 29, 2011
		Less than 12 months			More than 12 months
			Unrealized				Unrealized
(in millions)	Fair Value		Losses		Fair Value		Losses
Corporate debt securities	$	256	$	(1)	$	16	$	(5)
Auction rate securities		-		-		133		(34)
Mortgage-backed securities		161		(1)		67		(7)
U.S. government and agency securities		267		(1)		-		-
Other asset-backed securities		74		(1)		12		(2)
Total	$	758	$	(4)	$	228	$	(48)

At October 28, 2011 the Company concluded that the unrealized losses associated with the available-for-sale securities detailed above were not other-than-temporary as the Company does not have the intent to sell, nor is it more likely than not that the Company will be required to sell, before recovery of the amortized cost.

Activity related to the Company’s short-term and long-term investment portfolio is as follows:

	Three months ended
	October 28, 2011				October 29, 2010
(in millions)	Debt (a)		Equity (b)(c)		Debt (a)		Equity (b)
Proceeds from sales	$	1,406	$	12	$	1,609	$	-
Gross realized gains		14		50		10		-
Gross realized losses		(5)		-		(3)		-
Impairment losses recognized		-		(4)		(2)		(2)

	Six months ended
	October 28, 2011				October 29, 2010
(in millions)	Debt (a)		Equity (b)(c)		Debt (a)		Equity (b)
Proceeds from sales	$	2,967	$	53	$	2,793	$	-
Gross realized gains		24		55		17		-
Gross realized losses		(7)		-		(7)		-
Impairment losses recognized		(1)		(4)		(5)		(5)

(a) Includes available-for-sale debt securities.
(b) Includes marketable equity securities, cost method, equity method, exchange-traded funds, and other investments.
(c) As a result of the Salient and PEAK acquisitions, the Company recognized a non-cash gain of $38 million during the three months ended October 28, 2011 on its previously held minority investments.

The total other-than-temporary impairment losses on available-for-sale debt securities for the three and six months ended October 28, 2011 were $1 million and $3 million, respectively, of which $1 million and $2 million, respectively, were recognized in other comprehensive income resulting in less than $1 million and $1 million, respectively, of charges being recognized in earnings. The total other-than-temporary impairment losses on available-for-sale debt securities for the three and six months ended October 29, 2010 were $8 million and $17 million, respectively, of which $6 million and $12 million, respectively, were recognized in other comprehensive income resulting in $2 million and $5 million, respectively, of charges being recognized in earnings. These charges relate to credit losses on certain mortgage-backed securities and other asset-backed securities. The amount of credit losses represents the difference between the present value of cash flows expected to be collected on these securities and the amortized cost. Based on the Company's assessment of the credit quality of the underlying collateral and credit support available to each of the remaining securities in which it invested, the Company believes it has recorded all necessary other-than-temporary impairments as the Company does not have the intent to sell, nor is it more likely than not that the Company will be required to sell, before recovery of the amortized cost.

The following table shows the credit loss portion of other-than-temporary impairments on debt securities held by the Company as of the dates indicated and the corresponding changes in such amounts:

	Three months ended
(in millions)	October 28, 2011		October 29, 2010
Beginning Balance	$	20		19
Additional credit losses recognized on securities previously impaired		-		1
Credit losses recognized on securities previously not impaired		-		1
Ending Balance	$	20	$	21

	Six months ended
(in millions)	October 28, 2011		October 29, 2010
Beginning Balance	$	20		17
Additional credit losses recognized on securities previously impaired		-		3
Credit losses recognized on securities previously not impaired		1		2
Reductions for securities sold during the period		(1)		(1)
Ending Balance	$	20	$	21

The October 28, 2011 balance of available-for-sale debt securities by contractual maturity is shown in the following table at fair value. Within the table, maturities of mortgage-backed securities have been allocated based upon timing of estimated cash flows, assuming no change in the current interest rate environment. Actual maturities may differ from contractual maturities because the issuers of the securities may have the right to prepay obligations without prepayment penalties.

(in millions)	October 28,
(in millions)	2011
Due in one year or less	$	1,333
Due after one year through five years		4,936
Due after five years through ten years		669
Due after ten years		154
Total debt securities	$	7,092

As of October 28, 2011 and April 29, 2011, the aggregate carrying amount of equity and other securities without a quoted market price and accounted for using the cost or equity method was $831 million and $656 million, respectively. The total carrying value of these investments is reviewed quarterly for changes in circumstance or the occurrence of events that suggest the Company's investment may not be recoverable. The fair value of cost or equity method investments is not adjusted if there are no identified events or changes in circumstances that may have a material adverse effect on the fair value of the investment. The October 28, 2011 cost method, equity method, and other investments balance includes $464 million of investments in a public company which have trading restrictions through December 31, 2013. These investments will be reclassified to available-for-sale marketable equity securities when the restriction is within one year of lapsing.

Gains and losses realized on trading securities and available-for-sale debt securities are recorded in interest expense, net in the condensed consolidated statements of earnings. Gains and losses realized on marketable equity securities, cost method, equity method, and other investments are recorded in other expense (income) in the condensed consolidated statements of earnings. In addition, unrealized gains and losses on available-for-sale debt securities are recorded in accumulated other comprehensive loss in the condensed consolidated balance sheets and unrealized gains and losses on trading securities are recorded in interest expense, net in the condensed consolidated statements of earnings. Gains and losses from the sale of investments are calculated based on the specific identification method.