Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2012

The following weighted average assumptions were used to calculate the fair values of stock option grants in each year:



	2012		2011		2010
Risk free interest rate	1.3	%	2.9	%	2.8	%
Expected life of option in years	6.5		6.4		5.9
Expected dividend yield	3.3	%	3.3	%	3.4	%
Expected volatility	29.4	%	28.0	%	28.5	%

A summary of stock options outstanding and exercisable and activity for the year ended December 31, 2012 is presented below:



	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (in years)	Intrinsic Value (in millions)
Outstanding, January 1, 2012	4,907,885		$	60.52	5.6	$	116
Granted	792,957		$	90.28
Exercised	(2,251,975	)	$	54.10
Forfeited/Expired	(40,168	)	$	88.94
Outstanding, December 31, 2012	3,408,699		$	71.34	6.6	$	218
Vested or expected to vest, December 31, 2012	3,341,323		$	71.05	6.6	$	215
Exercisable, December 31, 2012	1,271,875		$	57.78	4.0	$	99

The following table presents stock option activity for the years ended December 31, 2012, 2011 and 2010:



(Millions)	2012		2011		2010
Total intrinsic value of stock options exercised	$	110	$	40	$	37
Cash received from stock option exercises	122		81		146
Income tax benefit from the exercise of stock options	35		9		9
Total fair value of stock options vested	6		10		13

The following table summarizes RSU activity for the year ended December 31, 2012:



	Number of Shares		Weighted Average Fair Value		Intrinsic Value (in millions)
Outstanding, January 1, 2012	1,005,757		$	46.98	$	84
Granted	248,732		$	83.48
Additional shares vested	208,228		$	55.30
Released from restrictions	(465,879	)	$	28.37
Forfeited	(42,902	)	$	53.68
Outstanding, December 31, 2012	953,936		$	67.11	$	129
Vested or expected to vest, December 31, 2012	945,429		$	66.97	$	128