| Year | Total Expenses | Average Net Price |
|---|---|---|
| 2015 | $20,972 | $16,257 |
| 2016 | $15,994 | $11,299 |
| 2017 | $16,014 | $11,098 |
| 2018 | $16,014 | $11,906 |
| 2019 | $16,950 | $12,013 |
| 2020 | $17,210 | $12,273 |
| 2021* | $17,232 | $12,383 |
| 2022* | $17,255 | $12,495 |
| 2023* | $17,277 | $12,607 |
| 2024* | $17,300 | $12,721 |
| 2025* | $17,322 | $12,835 |