Consolidated Statements of Income (USD $) In Millions, except Per Share data	12 Months Ended
May 31, 2011	May 31, 2010	May 31, 2009
Revenue:
Service revenue	$ 2,036.2	$ 1,945.8	$ 2,007.3
Interest on funds held for clients	48.1	55.0	75.5
Total revenue	2,084.3	2,000.8	2,082.8
Expenses:
Operating expenses	653.6	653.6	680.5
Selling, general and administrative expenses	644.3	622.4	597.1
Total expenses	1,297.9	1,276.0	1,277.6
Operating income	786.4	724.8	805.2
Investment income, net	5.8	4.5	6.9
Income before income taxes	792.2	729.3	812.1
Income taxes	276.9	252.3	278.6
Net income	$ 515.3	$ 477.0	$ 533.5
Basic earnings per share	$ 1.42	$ 1.32	$ 1.48
Diluted earnings per share	$ 1.42	$ 1.32	$ 1.48
Weighted-average common shares outstanding	361.8	361.4	360.8
Weighted-average common shares outstanding, assuming dilution	362.4	361.7	361.0
Cash dividends per common share	$ 1.24	$ 1.24	$ 1.24

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