Stock-Based Compensation Plans (Tables)

12 Months Ended

May 31, 2013

Stock-Based Compensation Plans [Abstract]

Weighted-average assumptions used for valuation under the Black-Scholes model

The weighted-average assumptions used for valuation under the Black-Scholes model are as follows:

	Year ended May 31,
	2013			2012			2013			2012			2011
	Performance stock options						Stock options
Risk-free interest rate	0.7		%	1.9		%	1.0		%	2.2		%	2.2		%
Dividend yield	4.1		%	4.2		%	4.3		%	4.2		%	4.2		%
Volatility factor	.22			.24			.23			.24			.24
Expected option life in years	4.8			5.8			6.4			6.4			6.5
Weighted-average grant-date fair value of stock options granted (per share)	$	3.55		$	4.35		$	3.77		$	4.46		$	4.02

Broad-based stock option grants

The Company had granted stock options to virtually all non-management employees with at least ninety of service, and shares remain outstanding for the following broad-based stock option grants:

Date of broad-based grant	Shares granted (millions)	Exercise price per  share		Shares outstanding as  of May 31, 2013 (millions)
April 2004	1.7	$	37.72	0.6
October 2006	2.0	$	37.32	1.0

Stock options activity

The following table summarizes stock option activity for the year ended May 31, 2013:

In millions, except per share amounts	Shares subject to options		Weighted-average exercise price per share		Weighted-average remaining contractual term (years)	Aggregate  intrinsic value(1)
Outstanding as of May 31, 2012	10.0		$	33.88
Granted	1.0		$	31.73
Exercised	(2.4	)	$	31.91
Forfeited	(0.1	)	$	29.33
Expired	(0.5	)	$	35.70
Outstanding as of May 31, 2013	8.0		$	34.17	4.4	$	26.3
Exercisable as of May 31, 2013	6.1		$	35.29	3.2	$	13.8

⁽¹⁾ Market price of the underlying stock as of May 31, 2013 less the exercise price.

Stock option plan other information

Other information pertaining to stock option grants is as follows:

	Year ended May 31,
In millions, except per share amounts	2013		2012		2011
Total intrinsic value of stock options exercised	$	7.8	$	0.8	$	1.9
Total grant-date fair value of stock options vested	$	3.0	$	10.4	$	20.0

Performance stock options activity

The following table summarizes performance stock option activity for the year ended May 31, 2013:

In millions, except per share amounts	Shares subject to options		Weighted-average exercise price per share		Weighted-average remaining contractual term (years)	Aggregate intrinsic value (2)
Outstanding as of May 31, 2012	2.6		$	30.80
Granted(1)	0.2		$	32.99
Exercised	—		$	—
Forfeited	(0.1	)	$	31.63
Expired	—		$	—
Outstanding as of May 31, 2013	2.7		$	30.95	8.3	$	16.8
Exercisable as of May 31, 2013	—		$	—	0.0	$	—

⁽¹⁾  Performance stock options granted assuming achievement of performance goals at target. Actual amount of shares to be earned may differ from this amount.

⁽²⁾  Market price of the underlying stock as of May 31, 2013 less the exercise price.

RSU Activity

The following table summarizes RSU activity for the year ended May 31, 2013:

In millions, except per share amounts	RSUs		Weighted-average grant-date fair value per share		Weighted-average remaining vesting period (years)	Aggregate  intrinsic value (1)
Nonvested as of May 31, 2012	1.6		$	25.49
Granted	0.7		$	28.59
Vested	(0.5	)	$	27.10
Forfeited	(0.2	)	$	25.96
Nonvested as of May 31, 2013	1.6		$	26.29	1.6	$	59.9

⁽¹⁾  An RSU is an agreement to issue shares at the time of vesting with no associated exercise cost. Therefore, intrinsic value for RSUs is the market price of the underlying stock as of May 31, 2013.

Other information pertaining to RSUs

Other information pertaining to RSUs is as follows:

	Year ended May 31,
In millions, except per share amounts	2013		2012		2011
Weighted-average grant-date fair value of RSUs granted	$	28.59	$	27.67	$	21.52
Total intrinsic value of RSUs vested	$	15.5	$	11.0	$	7.7
Total grant-date fair value of RSUs vested	$	13.4	$	9.5	$	8.5

Restricted stock award activity

The following table summarizes restricted stock activity for the year ended May 31, 2013:

In millions, except per share amounts	Restricted shares		Weighted-average grant-date fair value per share
Nonvested as of May 31, 2012	0.2		$	29.35
Granted	0.1		$	31.76
Vested	(0.1	)	$	31.06
Forfeited	—		$	29.19
Nonvested as of May 31, 2013	0.2		$	29.83

Other information pertaining to restricted stock awards

Other information pertaining to restricted stock follows:

	Year ended May 31,
In millions, except per share amounts	2013		2012		2011
Weighted-average grant-date fair value of restricted stock granted	$	31.76	$	30.69	$	26.40
Total grant-date fair value of restricted stock vested	$	2.1	$	3.2	$	2.2

Performance shares activity

The following table summarizes performance share activity for the year ended May 31, 2013:

In millions, except per share amounts	Performance shares	Weighted-average grant-date fair value per share
Nonvested as of May 31, 2012	0.2	$	26.83
Granted(1)	0.2	$	29.10
Forfeited	—	$	26.74
Nonvested as of May 31, 2013	0.4	$	27.89

⁽¹⁾  Performance shares granted assuming achievement of performance goals at target. Actual amount of shares to be earned may differ from this amount.