| Year | Total Expenses | Average Net Price |
|---|---|---|
| 2015 | $23,202 | $18,139 |
| 2016 | $23,508 | $17,153 |
| 2017 | $23,877 | $18,998 |
| 2018 | $23,877 | $19,142 |
| 2019 | $24,489 | $20,623 |
| 2020 | $26,472 | $22,606 |
| 2021* | $26,888 | $24,356 |
| 2022* | $27,310 | $26,241 |
| 2023* | $27,739 | $28,272 |
| 2024* | $28,174 | $30,460 |
| 2025* | $28,616 | $32,818 |