Table:
|  | Shares | Weighted Average Grant-Date Fair Value |
| --- | --- | --- |
| (In millions) |  |  |
| Stock Awards |  |  |
| Nonvested balance, beginning of year | 174 | $  57.85 |
| Granted (a) | 63 | 107.02 |
| Vested | (77) | 57.08 |
| Forfeited | (13) | 69.35 |
| Nonvested balance, end of year | 147 | $ 78.49 |
Paragraphs:
During fiscal year 2019, the following activity occurred under our stock plans:
(a) Includes 2 million, 3 million, and 2 million of PSUs granted at target and performance adjustments above target levels for fiscal years 2019, 2018, and 2017, respectively.
As of June 30, 2019, there was approximately $8.6 billion of total unrecognized compensation costs related to stock awards. These costs are expected to be recognized over a weighted average period of 3 years. The weighted average grant-date fair value of stock awards granted was $107.02, $75.88, and $55.64 for fiscal years 2019, 2018, and 2017, respectively. The fair value of stock awards vested was $8.7 billion, $6.6 billion, and $4.8 billion, for fiscal years 2019, 2018, and 2017, respectively.
Question:
What was the average fair value of stock awards vested over the 3 year period from 2017 to 2019?
Answer: (8.7+6.6+4.8)/3 = 6.7