| Year | Total Expenses | Average Net Price |
|---|---|---|
| 2015 | $32,694 | $24,533 |
| 2016 | $32,954 | $25,336 |
| 2017 | $32,894 | $24,380 |
| 2018 | $32,894 | $23,728 |
| 2019 | $32,986 | $22,909 |
| 2020 | $32,990 | $22,913 |
| 2021* | $32,993 | $22,301 |
| 2022* | $32,997 | $21,706 |
| 2023* | $33,000 | $21,126 |
| 2024* | $33,003 | $20,562 |
| 2025* | $33,006 | $20,013 |