| Year | Total Expenses | Average Net Price |
|---|---|---|
| 2015 | $19,962 | $16,110 |
| 2016 | $20,199 | $15,920 |
| 2017 | $20,922 | $16,739 |
| 2018 | $20,922 | $16,582 |
| 2019 | $21,851 | $17,281 |
| 2020 | $21,572 | $17,002 |
| 2021* | $21,829 | $16,842 |
| 2022* | $22,088 | $16,684 |
| 2023* | $22,351 | $16,527 |
| 2024* | $22,617 | $16,372 |
| 2025* | $22,886 | $16,218 |