Income Taxes	3 Months Ended
Mar. 30, 2019
Income Taxes
Income Taxes	Note 14. Income Taxes Our effective tax rate for the first quarter of 2019 and 2018 was 15.6% and 13.3%, respectively. In the first quarter of 2019, the effective tax rate was lower than the U.S. federal statutory tax rate of 21%, primarily due to a $12 million benefit recognized for additional research credits related to prior years. In the first quarter of 2018, the effective tax rate was lower than the U.S. federal statutory tax rate of 21%, primarily due to benefits recognized from audit settlements. Our reserve for unrecognized tax benefits totaled $175 million and $141 million at March 30, 2019 and December 29, 2018, respectively. The increase in this reserve largely reflects a claim filed in the first quarter of 2019 for tax credits related to prior years.

Income Taxes

3 Months Ended

Mar. 30, 2019

Note 14. Income Taxes

Our effective tax rate for the first quarter of 2019 and 2018 was 15.6% and 13.3%, respectively. In the first quarter of 2019, the effective tax rate was lower than the U.S. federal statutory tax rate of 21%, primarily due to a $12 million benefit recognized for additional research credits related to prior years. In the first quarter of 2018, the effective tax rate was lower than the U.S. federal statutory tax rate of 21%, primarily due to benefits recognized from audit settlements.

Our reserve for unrecognized tax benefits totaled $175 million and $141 million at March 30, 2019 and December 29, 2018, respectively. The increase in this reserve largely reflects a claim filed in the first quarter of 2019 for tax credits related to prior years.