| Year | Total Expenses | Average Net Price | 
|---|---|---|
| 2015 | $31,696 | $19,972 | 
| 2016 | $32,782 | $21,883 | 
| 2017 | $33,250 | $21,800 | 
| 2018 | $33,250 | $20,766 | 
| 2019 | $34,409 | $21,672 | 
| 2020 | $35,146 | $22,409 | 
| 2021* | $35,898 | $23,171 | 
| 2022* | $36,666 | $23,959 | 
| 2023* | $37,451 | $24,773 | 
| 2024* | $38,252 | $25,616 | 
| 2025* | $39,071 | $26,487 |