Table:
|  |  | Year Ended |  |
| --- | --- | --- | --- |
|  | January 3, 2020 | December 28, 2018 | December 29, 2017 |
| Expected volatility | 22.02% | 25.37% | 27.19% |
| Risk free rate of return | 2.39% | 2.35% | 1.53% |
| Weighted average grant date stock price | $62.66 | $65.00 | $53.73 |
Paragraphs:
The Monte Carlo simulation assumptions used for the periods presented were as follows:
As of January 3, 2020, there was $12 million of unrecognized compensation cost, net of estimated forfeitures, which is expected to be recognized over a weighted average period of 1.7 years. The fair value of performance-based stock awards that vested in fiscal 2019, 2018 and 2017 was $9 million, $13 million, and $4 million, respectively.
Question:
What was the change in the Expected volatility from 2017 to 2018?