Income taxes



	For the three months ended September 30				For the nine months ended September 30
(in millions of Canadian dollars)	2016		2015		2016		2015
Current income tax expense	$	73	$	159	$	177	$	364
Deferred income tax expense	50		—		233		106
Income tax expense	$	123	$	159	$	410	$	470

The estimated 2016 annual effective tax rate for the three and nine months ended September 30, 2016, excluding the discrete items related to the foreign exchange loss (gain) on the Company’s U.S. dollar-denominated debt and the settlement charge in respect of a corporate legal claim, is 25.17% and 26.50%, respectively, compared to the estimate of 27.50% for the same periods in 2015.

The effective tax rate for the three and nine months ended September 30, 2016, including the discrete items, is 26.23% and 25.26%, respectively, compared to 32.92% and 31.28%, respectively, for the same period in 2015.