26. Net Income per Share
| 2007 | 2006 | 2005 | ||||
| Basic net income per share1 | ||||||
Net income available to common shareholders |
$ | 1,103.6 | $ | 631.8 | $ | 542.9 |
Weighted average number of common shares |
315,641,000 | 311,880,000 | 325,704,000 | |||
Basic net income per share |
$ | 3.50 | $ | 2.03 | $ | 1.67 |
| Diluted net income per share1 | ||||||
Net income available to common shareholders |
$ | 1,103.6 | $ | 631.8 | $ | 542.9 |
Weighted average number of common shares |
315,641,000 | 311,880,000 | 325,704,000 | |||
Dilutive effect of stock options |
8,667,000 | 6,809,000 | 7,530,000 | |||
Weighted average number of diluted common shares |
324,308,000 | 318,689,000 | 333,234,000 | |||
Diluted net income per share |
$ | 3.40 | $ | 1.98 | $ | 1.63 |
Diluted net income per share is calculated based on the weighted average number of shares issued and outstanding during the year. The denominator is: (1) increased by the total of the additional common shares that would have been issued assuming exercise of all stock options with exercise prices at or below the average market price for the year; and (2) decreased by the number of shares that the company could have repurchased if it had used the assumed proceeds from the exercise of stock options to repurchase them on the open market at the average share price for the year. For performance-based stock option plans, the number of contingently issuable potential common shares included in the calculation is based on the number of shares that would be issuable based on period-to-date (rather than anticipated) performance, if the effect is dilutive.
No outstanding options were excluded from the calculation of diluted net income per share for 2007, 2006 or 2005 as a result of the options' exercise price being greater than the average market price of the common shares for the year.