| Year | Total Expenses | Average Net Price | 
|---|---|---|
| 2015 | $25,836 | $20,423 | 
| 2016 | $26,664 | $20,107 | 
| 2017 | $27,630 | $21,858 | 
| 2018 | $27,630 | $21,328 | 
| 2019 | $28,962 | $21,856 | 
| 2020 | $30,988 | $23,882 | 
| 2021* | $32,110 | $24,474 | 
| 2022* | $33,272 | $25,081 | 
| 2023* | $34,477 | $25,703 | 
| 2024* | $35,725 | $26,341 | 
| 2025* | $37,018 | $26,994 |