| Year | Total Expenses | Average Net Price | 
|---|---|---|
| 2015 | $20,172 | $13,397 | 
| 2016 | $21,334 | $14,522 | 
| 2017 | $23,094 | $15,565 | 
| 2018 | $23,094 | $14,860 | 
| 2019 | $24,352 | $15,744 | 
| 2020 | $24,352 | $15,744 | 
| 2021* | $25,679 | $16,681 | 
| 2022* | $27,079 | $17,673 | 
| 2023* | $28,554 | $18,725 | 
| 2024* | $30,111 | $19,839 | 
| 2025* | $31,752 | $21,019 |