(Millions of dollars) | Years ended December 31, | ||||||||||||||||||||
2013 | 2012 | 2011 | |||||||||||||||||||
Taxes at U.S. statutory rate | $ | 1,795 | 35.0 | % | $ | 2,882 | 35.0 | % | $ | 2,354 | 35.0 | % | |||||||||
(Decreases) increases in taxes resulting from: | |||||||||||||||||||||
Non-U.S. subsidiaries taxed at other than 35% | (268 | ) | (5.2 | )% | (342 | ) | (4.2 | )% | (467 | ) | (6.9 | )% | |||||||||
State and local taxes, net of federal | 23 | 0.4 | % | 55 | 0.7 | % | 30 | 0.4 | % | ||||||||||||
Interest and penalties, net of tax | 4 | 0.1 | % | 22 | 0.3 | % | 25 | 0.4 | % | ||||||||||||
U.S. research and production incentives | (91 | ) | (1.8 | )% | (80 | ) | (1.0 | )% | (152 | ) | (2.3 | )% | |||||||||
Other—net | (2 | ) | — | % | (27 | ) | (0.3 | )% | (7 | ) | (0.1 | )% | |||||||||
1,461 | 28.5 | % | 2,510 | 30.5 | % | 1,783 | 26.5 | % | |||||||||||||
Prior year tax and interest adjustments | (55 | ) | (1.1 | )% | (300 | ) | (3.7 | )% | 41 | 0.6 | % | ||||||||||
Nondeductible goodwill | — | — | % | 318 | 3.9 | % | 33 | 0.5 | % | ||||||||||||
Release of valuation allowances | — | — | % | — | — | % | (24 | ) | (0.3 | )% | |||||||||||
Non-U.S. earnings reinvestment changes | — | — | % | — | — | % | (113 | ) | (1.7 | )% | |||||||||||
Tax law changes | (87 | ) | (1.7 | )% | — | — | % | — | — | % | |||||||||||
Provision (benefit) for income taxes | $ | 1,319 | 25.7 | % | $ | 2,528 | 30.7 | % | $ | 1,720 | 25.6 | % | |||||||||