Table:
|  |  | Year Ended |  |
| --- | --- | --- | --- |
|  | January 3, 2020 | December 28, 2018 | December 29, 2017 |
|  |  | (in millions, except for per share amounts) |  |
| Favorable impact | $95 | $167 | $185 |
| Unfavorable impact | (52) | (62) | (82) |
| Net favorable impact to income before income taxes | $43 | $105 | $103 |
| Impact on diluted EPS attributable to Leidos common stockholders | $0.23 | $0.52 | $0.41 |
Paragraphs:
Changes in Estimates on Contracts
Changes in estimates related to contracts accounted for using the cost-to-cost method of accounting are recognized in the period in which such changes are made for the inception-to-date effect of the changes, with the exception of contracts acquired through a business combination, where the adjustment is made for the period commencing from the date of acquisition.
Changes in estimates on contracts for the periods presented were as follows:
The impact on diluted EPS attributable to Leidos common stockholders is calculated using the Company's statutory tax rate.
Question:
What is the change in the Net favorable impact to income before income taxes from 2018 to 2017?
Answer: 105 - 103 = 2