v2.4.0.6

Employee Benefit Plans (Tables) | 12 Months Ended
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Dec. 31, 2011
Pension and Postretirement Plans | An analysis of the projected benefit obligations for our pension plans and accumulated benefit obligations for our postretirement health and life insurance plans follows:
|  | Millions of Dollars |
|  | Pension Benefits |  |  | Other Benefits |
|  | 2011 |  |  | 2010 |  |  | 2011 |  |  | 2010 |
|  | U.S. |  |  | Int’l. |  |  | U.S. |  |  | Int’l. |  |  |  |  |  |  |
Change in Benefit Obligation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Benefit obligation at January 1 |  | $ | 5,539 |  |  |  | 3,206 |  |  |  | 5,042 |  |  |  | 3,101 |  |  |  | 862 |  |  |  | 839 |
Service cost |  |  | 225 |  |  |  | 98 |  |  |  | 229 |  |  |  | 90 |  |  |  | 10 |  |  |  | 11 |
Interest cost |  |  | 247 |  |  |  | 178 |  |  |  | 260 |  |  |  | 169 |  |  |  | 42 |  |  |  | 46 |
Plan participant contributions |  |  | — |  |  |  | 5 |  |  |  | — |  |  |  | 4 |  |  |  | 23 |  |  |  | 20 |
Government subsidy |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 4 |  |  |  | — |
Plan amendments |  |  | — |  |  |  | (53 | ) |  |  | 12 |  |  |  | — |  |  |  | 35 |  |  |  | — |
Actuarial loss |  |  | 642 |  |  |  | 195 |  |  |  | 305 |  |  |  | 59 |  |  |  | 20 |  |  |  | 14 |
Benefits paid |  |  | (478 | ) |  |  | (116 | ) |  |  | (309 | ) |  |  | (115 | ) |  |  | (68 | ) |  |  | (70 | )
Curtailment |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (1 | ) |  |  | — |  |  |  | — |
Foreign currency exchange rate change |  |  | — |  |  |  | (29 | ) |  |  | — |  |  |  | (101 | ) |  |  | (2 | ) |  |  | 2 |
Benefit obligation at December 31* |  | $ | 6,175 |  |  |  | 3,484 |  |  |  | 5,539 |  |  |  | 3,206 |  |  |  | 926 |  |  |  | 862 |
*Accumulatedbenefit obligation portion of above at December 31: |  | $ | 5,363 |  |  |  | 2,939 |  |  |  | 4,905 |  |  |  | 2,711 |  |  |  |  |  |  |  |  |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of plan assets at January 1 |  | $ | 3,890 |  |  |  | 2,581 |  |  |  | 3,144 |  |  |  | 2,281 |  |  |  | — |  |  |  | — |
Actual return on plan assets |  |  | 64 |  |  |  | 53 |  |  |  | 458 |  |  |  | 259 |  |  |  | — |  |  |  | — |
Company contributions |  |  | 673 |  |  |  | 226 |  |  |  | 597 |  |  |  | 216 |  |  |  | 41 |  |  |  | 50 |
Plan participant contributions |  |  | — |  |  |  | 5 |  |  |  | — |  |  |  | 4 |  |  |  | 23 |  |  |  | 20 |
Government subsidy |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 4 |  |  |  | — |
Benefits paid |  |  | (478 | ) |  |  | (116 | ) |  |  | (309 | ) |  |  | (115 | ) |  |  | (68 | ) |  |  | (70 | )
Curtailment |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (1 | ) |  |  | — |  |  |  | — |
Foreign currency exchange rate change |  |  | — |  |  |  | (27 | ) |  |  | — |  |  |  | (63 | ) |  |  | — |  |  |  | — |
Fair value of plan assets at December 31 |  | $ | 4,149 |  |  |  | 2,722 |  |  |  | 3,890 |  |  |  | 2,581 |  |  |  | — |  |  |  | — |
Funded Status |  | $ | (2,026 | ) |  |  | (762 | ) |  |  | (1,649 | ) |  |  | (625 | ) |  |  | (926 | ) |  |  | (862 | )
Amounts Recognized in Consolidated Balance Sheet |
|  | Millions of Dollars |
|  | Pension Benefits |  |  | Other Benefits |
|  | 2011 |  |  | 2010 |  |  | 2011 |  |  | 2010 |
|  | U.S. |  |  | Int’l. |  |  | U.S. |  |  | Int’l. |  |  |  |  |  |  |
Amounts Recognized in the Consolidated Balance Sheet at December 31 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Noncurrent assets |  | $ | — |  |  |  | 94 |  |  |  | — |  |  |  | 156 |  |  |  | — |  |  |  | — |
Current liabilities |  |  | (118 | ) |  |  | (5 | ) |  |  | (74 | ) |  |  | (4 | ) |  |  | (62 | ) |  |  | (51 | )
Noncurrent liabilities |  |  | (1,908 | ) |  |  | (851 | ) |  |  | (1,575 | ) |  |  | (777 | ) |  |  | (864 | ) |  |  | (811 | )
Total recognized |  | $ | (2,026 | ) |  |  | (762 | ) |  |  | (1,649 | ) |  |  | (625 | ) |  |  | (926 | ) |  |  | (862 | )
Weighted-Average Assumptions Used to Determine Benefit Obligations and Net Periodic Benefit Cost |
Weighted-Average Assumptions Used to Determine Benefit Obligations at December 31 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  |  | 4.30 | % |  |  | 4.90 |  |  |  | 4.65 |  |  |  | 5.40 |  |  |  | 4.40 |  |  |  | 5.00 |
Rate of compensation increase |  |  | 4.25 |  |  |  | 4.30 |  |  |  | 4.00 |  |  |  | 4.10 |  |  |  | — |  |  |  | — |
Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost for Years Ended December 31 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  |  | 4.65 | % |  |  | 5.40 |  |  |  | 5.35 |  |  |  | 5.80 |  |  |  | 5.00 |  |  |  | 5.60 |
Expected return on plan assets |  |  | 7.00 |  |  |  | 6.40 |  |  |  | 7.00 |  |  |  | 6.50 |  |  |  | — |  |  |  | — |
Rate of compensation increase |  |  | 4.00 |  |  |  | 4.10 |  |  |  | 4.00 |  |  |  | 4.50 |  |  |  | — |  |  |  | —
Before Tax Amounts Not Been Recognized in Net Periodic Postretirement Benefit Cost | Included in accumulated other comprehensive income at December 31 were the following before-tax amounts that had not been recognized in net periodic benefit cost:
|  | Millions of Dollars |
|  | Pension Benefits |  |  | Other Benefits |
|  | 2011 |  |  | 2010 |  |  | 2011 |  |  | 2010 |
|  | U.S. |  |  | Int’l. |  |  | U.S. |  |  | Int’l. |  |  |  |  |  |  |
Unrecognized net actuarial loss (gain) |  | $ | 2,240 |  |  |  | 705 |  |  |  | 1,567 |  |  |  | 444 |  |  |  | (26 | ) |  |  | (51 | )
Unrecognized prior service cost (credit) |  |  | 52 |  |  |  | (78 | ) |  |  | 61 |  |  |  | (25 | ) |  |  | (13 | ) |  |  | (54 | )
Sources of Change in Other Comprehensive Income |
|  | Millions of Dollars |
|  | Pension Benefits |  |  | Other Benefits |
|  | 2011 |  |  | 2010 |  |  | 2011 |  |  | 2010 |
|  | U.S. |  |  | Int’l. |  |  | U.S. |  |  | Int’l. |  |  |  |  |  |  |
Sources of Change in Other Comprehensive Income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net gain (loss) arising during the period |  | $ | (858 | ) |  |  | (307 | ) |  |  | (70 | ) |  |  | 75 |  |  |  | (20 | ) |  |  | (14 | )
Amortization of (gain) loss included in income |  |  | 185 |  |  |  | 46 |  |  |  | 167 |  |  |  | 55 |  |  |  | (5 | ) |  |  | (7 | )
Net change during the period |  | $ | (673 | ) |  |  | (261 | ) |  |  | 97 |  |  |  | 130 |  |  |  | (25 | ) |  |  | (21 | )
Prior service (cost) credit arising during the period |  | $ | — |  |  |  | 53 |  |  |  | (12 | ) |  |  | (1 | ) |  |  | (34 | ) |  |  | — |
Amortization of prior service cost (credit) included in income |  |  | 9 |  |  |  | — |  |  |  | 10 |  |  |  | 2 |  |  |  | (7 | ) |  |  | 3 |
Net change during the period |  | $ | 9 |  |  |  | 53 |  |  |  | (2 | ) |  |  | 1 |  |  |  | (41 | ) |  |  | 3 |
Amounts Included in Accumulated Other Comprehensive Income that are Expected to be Amortized into Net Periodic Postretirement Cost | Amounts included in accumulated other comprehensive income at December 31, 2011, that are expected to be amortized into net periodic postretirement cost during 2012 are provided below:
|  | Millions of Dollars |
|  | Pension Benefits |  |  | Other Benefits |
|  | U.S. |  |  | Int’l. |  |  |  |
Unrecognized net actuarial loss (gain) |  | $ | 235 |  |  |  | 71 |  |  |  | (3 | )
Unrecognized prior service cost |  |  | 9 |  |  |  | (9 | ) |  |  | (4 | )
Net Periodic Benefit Cost Related to Continuing and Discontinued Operations of All Defined Benefit Plans | The components of net periodic benefit cost related to continuing and discontinued operations of all defined benefit plans are presented in the following table:
|  | Millions of Dollars |
|  | Pension Benefits |  |  | Other Benefits |
|  | 2011 |  |  | 2010 |  |  | 2009 |  |  | 2011 |  |  | 2010 |  |  | 2009 |
|  | U.S. |  |  | Int’l. |  |  | U.S. |  |  | Int’l. |  |  | U.S. |  |  | Int’l. |  |  |  |  |  |  |  |  |  |
Components of Net Periodic Benefit Cost |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 225 |  |  |  | 98 |  |  |  | 229 |  |  |  | 90 |  |  |  | 194 |  |  |  | 79 |  |  |  | 10 |  |  |  | 11 |  |  |  | 9 |
Interest cost |  |  | 247 |  |  |  | 178 |  |  |  | 260 |  |  |  | 169 |  |  |  | 277 |  |  |  | 144 |  |  |  | 42 |  |  |  | 46 |  |  |  | 47 |
Expected return on plan assets |  |  | (280 | ) |  |  | (175 | ) |  |  | (224 | ) |  |  | (147 | ) |  |  | (184 | ) |  |  | (125 | ) |  |  | — |  |  |  | — |  |  |  | — |
Amortization of prior service cost (credit) |  |  | 9 |  |  |  | — |  |  |  | 10 |  |  |  | 2 |  |  |  | 11 |  |  |  | 1 |  |  |  | (7 | ) |  |  | 3 |  |  |  | 9 |
Recognized net actuarial loss (gain) |  |  | 165 |  |  |  | 46 |  |  |  | 167 |  |  |  | 55 |  |  |  | 186 |  |  |  | 35 |  |  |  | (5 | ) |  |  | (7 | ) |  |  | (15 | )
Net periodic benefit cost |  | $ | 366 |  |  |  | 147 |  |  |  | 442 |  |  |  | 169 |  |  |  | 484 |  |  |  | 134 |  |  |  | 40 |  |  |  | 53 |  |  |  | 50 |
Fair Values of Our Pension Plan Assets | The fair values of our pension plan assets at December 31, by asset class were as follows:
|  | Millions of Dollars |
|  | U.S. |  |  | International |
|  | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Total |  |  | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Total |
2011 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity Securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. |  | $ | 1,251 |  |  |  | — |  |  |  | — |  |  |  | 1,251 |  |  |  | 413 |  |  |  | — |  |  |  | — |  |  |  | 413 |
International |  |  | 803 |  |  |  | — |  |  |  | — |  |  |  | 803 |  |  |  | 413 |  |  |  | — |  |  |  | — |  |  |  | 413 |
Common/collective trusts |  |  | — |  |  |  | 634 |  |  |  | — |  |  |  | 634 |  |  |  | — |  |  |  | 234 |  |  |  | — |  |  |  | 234 |
Mutual funds |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 246 |  |  |  | — |  |  |  | — |  |  |  | 246 |
Debt Securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Government |  |  | 311 |  |  |  | 81 |  |  |  | — |  |  |  | 392 |  |  |  | 532 |  |  |  | — |  |  |  | — |  |  |  | 532 |
Corporate |  |  | — |  |  |  | 551 |  |  |  | 3 |  |  |  | 554 |  |  |  | — |  |  |  | 122 |  |  |  | 1 |  |  |  | 123 |
Agency and mortgage-backed securities |  |  | — |  |  |  | 105 |  |  |  | — |  |  |  | 105 |  |  |  | — |  |  |  | 43 |  |  |  | — |  |  |  | 43 |
Common/collective trusts |  |  | — |  |  |  | 249 |  |  |  | — |  |  |  | 249 |  |  |  | — |  |  |  | 346 |  |  |  | — |  |  |  | 346 |
Mutual funds |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 130 |  |  |  | — |  |  |  | — |  |  |  | 130 |
Cash and cash equivalents |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 32 |  |  |  | 26 |  |  |  | — |  |  |  | 58 |
Private equity funds |  |  | — |  |  |  | — |  |  |  | 4 |  |  |  | 4 |  |  |  | — |  |  |  | — |  |  |  | 13 |  |  |  | 13 |
Derivatives |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 11 |  |  |  | — |  |  |  | 11 |
Insurance contracts |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 15 |  |  |  | 15 |
Real estate |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 139 |  |  |  | 139 |
Total* |  | $ | 2,365 |  |  |  | 1,620 |  |  |  | 7 |  |  |  | 3,992 |  |  |  | 1,766 |  |  |  | 782 |  |  |  | 168 |  |  |  | 2,716 |
* | Excludes the participating interest in the annuity contract with a net asset value of $144 million and net receivables related to security transactions of $19 million.
2010 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity Securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. |  | $ | 1,250 |  |  |  | — |  |  |  | — |  |  |  | 1,250 |  |  |  | 378 |  |  |  | — |  |  |  | — |  |  |  | 378 |
International |  |  | 818 |  |  |  | — |  |  |  | — |  |  |  | 818 |  |  |  | 498 |  |  |  | — |  |  |  | — |  |  |  | 498 |
Common/collective trusts |  |  | — |  |  |  | 635 |  |  |  | — |  |  |  | 635 |  |  |  | — |  |  |  | 246 |  |  |  | — |  |  |  | 246 |
Mutual funds |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 282 |  |  |  | — |  |  |  | — |  |  |  | 282 |
Debt Securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Government |  |  | 251 |  |  |  | 56 |  |  |  | — |  |  |  | 307 |  |  |  | 390 |  |  |  | — |  |  |  | — |  |  |  | 390 |
Corporate |  |  | — |  |  |  | 420 |  |  |  | 3 |  |  |  | 423 |  |  |  | — |  |  |  | 171 |  |  |  | 2 |  |  |  | 173 |
Agency and mortgage-backed securities |  |  | — |  |  |  | 81 |  |  |  | — |  |  |  | 81 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Common/collective trusts |  |  | — |  |  |  | 270 |  |  |  | — |  |  |  | 270 |  |  |  | — |  |  |  | 329 |  |  |  | — |  |  |  | 329 |
Mutual funds |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 122 |  |  |  | — |  |  |  | — |  |  |  | 122 |
Cash and cash equivalents |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 9 |  |  |  | 10 |  |  |  | — |  |  |  | 19 |
Private equity funds |  |  | — |  |  |  | — |  |  |  | 6 |  |  |  | 6 |  |  |  | — |  |  |  | — |  |  |  | 8 |  |  |  | 8 |
Derivatives |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 12 |  |  |  | — |  |  |  | 12 |
Insurance contracts |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 16 |  |  |  | 16 |
Real estate |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 101 |  |  |  | 101 |
Total* |  | $ | 2,319 |  |  |  | 1,462 |  |  |  | 9 |  |  |  | 3,790 |  |  |  | 1,679 |  |  |  | 768 |  |  |  | 127 |  |  |  | 2,574 |
* | Excludes the participating interest in the annuity contract with a net asset value of $92 million and net receivables related to security transactions of $15 million.
Benefit Payments Exclusive Amount to be Paid From Participating Annuity Contract and Which Reflect Expected Future Service, as Appropriate, are Expected to be Paid | The following benefit payments, which are exclusive of amounts to be paid from the participating annuity contract and which reflect expected future service, as appropriate, are expected to be paid:
|  | Millions of Dollars |
|  | Pension Benefits |  |  | Other Benefits |
|  | U.S. |  |  | Int’l. |  |  |  |
2012 |  | $ | 577 |  |  |  | 110 |  |  |  | 63 |
2013 |  |  | 501 |  |  |  | 113 |  |  |  | 64 |
2014 |  |  | 524 |  |  |  | 121 |  |  |  | 67 |
2015 |  |  | 553 |  |  |  | 129 |  |  |  | 70 |
2016 |  |  | 598 |  |  |  | 134 |  |  |  | 72 |
2017-2021 |  |  | 3,206 |  |  |  | 794 |  |  |  | 385 |
CPSP Stock Savings Feature Shares | The total CPSP stock savings feature shares as of December 31 were:
|  | 2011 |  |  | 2010 |
Unallocated shares |  |  | 811,963 |  |  |  | 3,385,778 |
Allocated shares |  |  | 19,315,372 |  |  |  | 19,198,502 |
Total shares |  |  | 20,127,335 |  |  |  | 22,584,280 |
Share-Based Compensation Expense Recognized in Income Related to Continuing and Discontinued Operations and Associated Tax Benefit | Total share-based compensation expense recognized in income related to continuing and discontinued operations and the associated tax benefit for the years ended December 31, were as follows:
|  | Millions of Dollars |
|  | 2011 |  |  | 2010 |  |  | 2009 |
Compensation cost |  | $ | 246 |  |  |  | 211 |  |  |  | 121 |
Tax benefit |  |  | 86 |  |  |  | 78 |  |  |  | 42 |
Summary of Stock Option Activity for Three Years Ended December 31, 2011 | The following summarizes our stock option activity for the three years ended December 31, 2011:
|  |  |  |  | Weighted- |  |  | Weighted-Average |  |  | Millions of Dollars |
|  | Options |  |  | Average Exercise Price |  |  | Grant-Date Fair Value |  |  | Aggregate Intrinsic Value |
Outstanding at December 31, 2008 |  |  | 36,615,753 |  |  | $ | 35.65 |  |  |  |  |  |  |  |  |
Granted |  |  | 3,311,200 |  |  |  | 45.47 |  |  | $ | 11.18 |  |  |  |  |
Exercised |  |  | (2,919,118 | ) |  |  | 24.10 |  |  |  |  |  |  | $ | 67 |
Forfeited |  |  | (332,941 | ) |  |  | 52.04 |  |  |  |  |  |  |  |  |
Expired or canceled |  |  | (241,421 | ) |  |  | 63.49 |  |  |  |  |  |  |  |  |
Outstanding at December 31, 2009 |  |  | 36,433,473 |  |  | $ | 37.13 |  |  |  |  |  |  |  |  |
Granted |  |  | 3,040,500 |  |  |  | 48.39 |  |  | $ | 11.70 |  |  |  |  |
Exercised |  |  | (6,401,483 | ) |  |  | 29.08 |  |  |  |  |  |  | $ | 183 |
Forfeited |  |  | (255,889 | ) |  |  | 48.42 |  |  |  |  |  |  |  |  |
Expired or canceled |  |  | (204,727 | ) |  |  | 58.94 |  |  |  |  |  |  |  |  |
Outstanding at December 31, 2010 |  |  | 32,611,874 |  |  | $ | 39.54 |  |  |  |  |  |  |  |  |
Granted |  |  | 1,907,000 |  |  |  | 70.13 |  |  | $ | 16.70 |  |  |  |  |
Exercised |  |  | (10,022,685 | ) |  |  | 30.08 |  |  |  |  |  |  | $ | 416 |
Forfeited |  |  | (82,434 | ) |  |  | 62.26 |  |  |  |  |  |  |  |  |
Expired or canceled |  |  | (41,704 | ) |  |  | 51.60 |  |  |  |  |  |  |  |  |
Outstanding at December 31, 2011 |  |  | 24,372,051 |  |  | $ | 45.73 |  |  |  |  |  |  |  |  |
Vested at December 31, 2011 |  |  | 22,214,254 |  |  | $ | 44.49 |  |  |  |  |  |  | $ | 611 |
Exercisable at December 31, 2011 |  |  | 19,666,959 |  |  | $ | 43.19 |  |  |  |  |  |  | $ | 564 |
Significant Assumptions Used to Calculate Fair Market Values | The significant assumptions used to calculate the fair market values of the options granted over the past three years, as calculated using the Black-Scholes-Merton option-pricing model, were as follows:
|  | 2011 |  |  | 2010 |  |  | 2009 |
Assumptions used |  |  |  |  |  |  |  |  |  |  |  |
Risk-free interest rate |  |  | 3.10 | % |  |  | 3.23 |  |  |  | 2.90 |
Dividend yield |  |  | 4.00 | % |  |  | 4.00 |  |  |  | 3.50 |
Volatility factor |  |  | 33.40 | % |  |  | 33.80 |  |  |  | 32.90 |
Expected life (years) |  |  | 6.87 |  |  |  | 6.65 |  |  |  | 6.53 |
The ranges in the assumptions used were as follows:
|  | 2011 |  |  | 2010 |  |  | 2009 |
|  | High |  |  | Low |  |  | High |  |  | Low |  |  | High |  |  | Low |
Ranges used |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk-free interest rate |  |  | 3.10 | % |  |  | 3.10 |  |  |  | 3.23 |  |  |  | 3.23 |  |  |  | 2.90 |  |  |  | 2.90 |
Dividend yield |  |  | 4.00 |  |  |  | 4.00 |  |  |  | 4.00 |  |  |  | 4.00 |  |  |  | 3.50 |  |  |  | 3.50 |
Volatility factor |  |  | 33.40 |  |  |  | 33.40 |  |  |  | 33.80 |  |  |  | 33.80 |  |  |  | 32.90 |  |  |  | 32.90 |
Summary of Restricted Stock Unit Activity | The following summarizes our stock unit activity for the three years ended December 31, 2011:
|  |  |  |  | Weighted-Average |  |  | Millions of Dollars |
|  | Stock Units |  |  | Grant-Date Fair Value |  |  | Total Fair Value |
Outstanding at December 31, 2008 |  |  | 5,927,698 |  |  | $ | 61.14 |  |  |  |  |
Granted |  |  | 2,910,095 |  |  |  | 43.41 |  |  |  |  |
Forfeited |  |  | (207,932 | ) |  |  | 51.84 |  |  |  |  |
Issued |  |  | (1,910,309 | ) |  |  |  |  |  | $ | 88 |
Outstanding at December 31, 2009 |  |  | 6,719,552 |  |  | $ | 57.08 |  |  |  |  |
Granted |  |  | 2,890,010 |  |  |  | 46.38 |  |  |  |  |
Forfeited |  |  | (233,212 | ) |  |  | 53.11 |  |  |  |  |
Issued |  |  | (1,573,487 | ) |  |  |  |  |  | $ | 79 |
Outstanding at December 31, 2010 |  |  | 7,802,863 |  |  | $ | 53.04 |  |  |  |  |
Granted |  |  | 2,746,045 |  |  |  | 67.54 |  |  |  |  |
Forfeited |  |  | (299,531 | ) |  |  | 56.43 |  |  |  |  |
Issued |  |  | (1,520,419 | ) |  |  |  |  |  | $ | 109 |
Outstanding at December 31, 2011 |  |  | 8,728,958 |  |  | $ | 55.41 |  |  |  |  |
Not Vested at December 31, 2011 |  |  | 6,175,477 |  |  | $ | 55.93 |  |  |  |  |
Summary of Performance Share Program Activity | The following summarizes our Performance Share Program activity for the three years ended December 31, 2011:
|  | Performance |  |  | Weighted-Average |  |  | Millions of Dollars |
|  | Share Units |  |  | Grant-Date Fair Value |  |  | Total Fair Value |
Outstanding at December 31, 2008 |  |  | 3,176,178 |  |  | $ | 68.13 |  |  |  |  |
Granted |  |  | 659,812 |  |  |  | 45.47 |  |  |  |  |
Forfeited |  |  | (23,670 | ) |  |  | 65.00 |  |  |  |  |
Issued |  |  | (407,442 | ) |  |  |  |  |  | $ | 19 |
Outstanding at December 31, 2009 |  |  | 3,404,878 |  |  | $ | 64.63 |  |  |  |  |
Granted |  |  | 317,072 |  |  |  | 48.39 |  |  |  |  |
Forfeited |  |  | (53,243 | ) |  |  | 62.66 |  |  |  |  |
Issued |  |  | (234,121 | ) |  |  |  |  |  | $ | 12 |
Outstanding at December 31, 2010 |  |  | 3,434,586 |  |  | $ | 63.43 |  |  |  |  |
Granted |  |  | 615,780 |  |  |  | 70.57 |  |  |  |  |
Forfeited |  |  | (23,240 | ) |  |  | 63.18 |  |  |  |  |
Issued |  |  | (509,365 | ) |  |  |  |  |  | $ | 37 |
Outstanding at December 31, 2011 |  |  | 3,517,761 |  |  | $ | 64.35 |  |  |  |  |
Not Vested at December 31, 2011 |  |  | 1,063,982 |  |  | $ | 64.16 |  |  |  |  |
Summary of Aggregate Activity of Restricted Shares and Units | The following summarizes the aggregate activity of these restricted shares and units for the three years ended December 31, 2011:
|  |  |  |  | Weighted-Average |  |  | Millions of Dollars |
|  | Stock Units |  |  | Grant-Date Fair Value |  |  | Total Fair Value |
Outstanding at December 31, 2008 |  |  | 3,364,020 |  |  | $ | 36.75 |  |  |  |  |
Granted |  |  | 78,299 |  |  |  | 45.72 |  |  |  |  |
Issued |  |  | (204,160 | ) |  |  |  |  |  | $ | 10 |
Canceled |  |  | (101,642 | ) |  |  | 52.91 |  |  |  |  |
Outstanding at December 31, 2009 |  |  | 3,136,517 |  |  | $ | 35.11 |  |  |  |  |
Granted |  |  | 73,395 |  |  |  | 53.33 |  |  |  |  |
Issued |  |  | (181,035 | ) |  |  |  |  |  | $ | 9 |
Canceled |  |  | (58,441 | ) |  |  | 44.23 |  |  |  |  |
Outstanding at December 31, 2010 |  |  | 2,970,436 |  |  | $ | 34.06 |  |  |  |  |
Granted |  |  | 76,642 |  |  |  | 70.25 |  |  |  |  |
Issued |  |  | (139,523 | ) |  |  |  |  |  | $ | 10 |
Canceled |  |  | (319,640 | ) |  |  | 30.90 |  |  |  |  |
Outstanding at December 31, 2011 |  |  | 2,587,915 |  |  | $ | 33.49 |  |  |  |  |
Not Vested at December 31, 2011 |  |  | — |  |  |  |  |  |  |  |  |

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- Definition Tabular disclosure of the amounts that are recognized in the balance sheet (or statement of financial position) for pension plans and/or other employee benefit plans, showing separately the assets and current and noncurrent liabilities (if applicable) recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the net gain (loss) and net prior service cost or credit recognized in other comprehensive income (loss) for the period for pension plans and/or other employee benefit plans, and reclassification adjustments of other comprehensive income (loss) for the period, as those amounts, including amortization of the net transition asset or obligation, are recognized as components of net periodic benefit cost. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the assumptions used to determine for pension plans and/or other employee benefit plans the benefit obligation and net benefit cost, including assumed discount rates, rate increase in compensation increase, and expected long-term rates of return on plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the aggregate benefit obligation and aggregate fair value of plan assets for pension plans and/or other employee benefit plans with benefit obligations in excess of plan assets as of the measurement date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e2417-114920 + Details
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- Definition Tabular disclosure of the amount of total share-based compensation cost, including the amounts attributable to each share-based compensation plan and any related tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the description of the plan, the basis for determining contributions, including the employee groups covered, and the nature and effect of significant matters affecting comparability of information for all periods presented. For leveraged ESOPs and pension reversion ESOPs, the disclosure may include the basis for releasing shares and how dividends on allocated and unallocated shares are used. Disclosure may also include a description of the accounting policies followed for ESOP transactions, including the method of measuring compensation, the classification of dividends on ESOP shares, and the treatment of ESOP shares for EPS computations. If the employer has both old ESOP shares for which it does not adopt the latest guidance and new ESOP shares for which the new guidance is required, the accounting policies for both blocks of shares may be described. Disclosure may also include he amount of compensation cost recognized during the period, the number of allocated shares, committed-to-be-released shares, and suspense shares held by the ESOP at the balance-sheet date, the fair value of unearned ESOP shares at the balance-sheet date for shares accounted for under the latest guidance, the existence and nature of any repurchase obligation, including disclosure of the fair value of the shares allocated as of the balance sheet date, which are subject to a repurchase obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 93-6 -Paragraph 53 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the amounts related to pension plans and/or other employee benefit plans in accumulated other comprehensive income or loss that have not yet been recognized as components of net periodic benefit cost, such as the net gain (loss), net prior service cost or credit, and net transition asset or obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the changes in outstanding nonvested performance-based units. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Disclosure of the number and weighted-average grant date fair value for restricted stock and restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock and restricted stock units that were granted, vested, or forfeited during the year. + References No definition available. + Details
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- Definition Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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