| Year | Total Expenses | Average Net Price |
|---|---|---|
| 2015 | $29,544 | $28,033 |
| 2016 | $29,004 | $25,670 |
| 2017 | $28,626 | $24,249 |
| 2018 | $28,626 | $23,393 |
| 2019 | $28,284 | $26,760 |
| 2020 | $25,041 | $23,517 |
| 2021* | $24,715 | $22,214 |
| 2022* | $24,394 | $20,983 |
| 2023* | $24,077 | $19,821 |
| 2024* | $23,764 | $18,723 |
| 2025* | $23,455 | $17,686 |