Stock Plans (Tables)

12 Months Ended

Dec. 31, 2013

Summary of Stock Option and RSA Activity

A summary of stock option and RSA activity as of December 31, 2013, and changes during the year is presented below:

			Stock Options			RSAs
(Shares in thousands)			Shares	Weighted-Average Exercise Price		Shares	Weighted- Average Grant Price
Outstanding as of
	December 31, 2012		31,861	$	43.62	11,800	$	40.31
Granted			463		61.76	3,867		60.13
Exercised/vested			(13,672)		42.39	(5,559)		33.24
Forfeited			(22)		39.25	(530)		50.31
Expired			(15)		45.61	―		―
Outstanding as of
	December 31, 2013		18,615		44.98	9,578	$	51.88
Options vested and
	expected to vest as of
		December 31, 2013	18,600		44.98	―		―
Options exercisable as of
	December 31, 2013		16,842	$	44.51	―		―

Weighted-average remaining contractual life and aggregate intrinsic value of the Company's stock options outstanding, exerciseable, and vested and expected to vest

The weighted-average remaining contractual life and the aggregate intrinsic value (the amount by which the fair value of the Company's stock exceeds the exercise price of the option) of the stock options outstanding, exercisable, and vested and expected to vest as of December 31, 2013 are as follows:

		Outstanding		Exercisable		Vested and Expected to Vest
Weighted-average remaining
	contractual life (in years)		4.4		4.0		4.4
Aggregate intrinsic value (millions)		$	852	$	778	$	851

Weighted Average Assumptions Used

The fair value of each option is estimated on the date of grant using a Black-Scholes-Merton option-pricing model. The following weighted-average assumptions were used for grants issued in 2013, 2012 and 2011, the majority of which were granted in the beginning of each year:

	2013			2012			2011
Dividend yield		1.4	%		1.5	%		1.6	%
Expected volatility^(a)		39	%		41	%		40	%
Risk-free interest rate		1.3	%		1.3	%		2.3	%
Expected life of stock option (in years)^(b)		6.3			6.3			6.2
Weighted-average fair value per option	$	21.11		$	17.48		$	16.21

The expected volatility is based on both weighted historical and implied volatilities of the Company's common stock price.
In 2013, 2012 and 2011, the expected life of stock options was determined using both historical data and expectations of option exercise behavior.

Summary of Stock Plan Expenses

The components of the Company's total stock-based compensation expense (net of forfeitures) for the years ended December 31 are as follows:

(Millions)		2013		2012		2011
Restricted stock awards^(a)		$	208	$	197	$	176
Stock options^(a)			23		29		40
Liability-based awards			119		70		83
Performance/market-based
	stock options		―		1		2
Total stock-based
	compensation expense^(b)	$	350	$	297	$	301

As of December 31, 2013, the total unrecognized compensation cost related to unvested RSAs and options of $232 million and $14 million, respectively, will be recognized ratably over the weighted-average remaining vesting period of 2.1 years and 1.8 years, respectively.
The total income tax benefit recognized in the Consolidated Statements of Income for stock-based compensation arrangements for the years ended December 31, 2013, 2012 and 2011 was $127 million, $107 million and $105 million, respectively.