Income taxes

9 Months Ended

Sep. 30, 2021

Income Tax Disclosure [Abstract]

Income taxes

Income taxes

Our estimated annual effective tax rate is about 14%, which does not include discrete tax items. This differs from the 21% U.S. statutory corporate tax rate due to the effect of U.S. tax benefits.

Provision for income taxes is based on the following:

	For Three Months Ended						For Nine Months Ended
	September 30,						September 30,
	2021			2020			2021			2020
Taxes calculated using the estimated annual effective tax rate	$	337		$	231		$	934		$	561
Discrete tax items	(9)			3			(109)			(378)
Provision for income taxes	$	328		$	234		$	825		$	183
Effective tax rate	14		%	15		%	13		%	4		%

Our provision for income taxes for the first nine months of 2020 included a $249 million discrete tax benefit for the settlement of a depreciation-related uncertain tax position. Accrued interest of $46 million related to this uncertain tax position was reversed and included in OI&E.