| Year | Total Expenses | Average Net Price |
|---|---|---|
| 2015 | $19,694 | $16,191 |
| 2016 | $19,900 | $16,384 |
| 2017 | $20,070 | $16,664 |
| 2018 | $20,070 | $16,621 |
| 2019 | $20,822 | $16,913 |
| 2020 | $21,111 | $17,202 |
| 2021* | $21,333 | $17,496 |
| 2022* | $21,557 | $17,795 |
| 2023* | $21,783 | $18,100 |
| 2024* | $22,012 | $18,409 |
| 2025* | $22,243 | $18,724 |