| Year | Total Expenses | Average Net Price | 
|---|---|---|
| 2015 | $16,606 | $11,816 | 
| 2016 | $16,602 | $11,139 | 
| 2017 | $17,120 | $11,855 | 
| 2018 | $17,120 | $11,752 | 
| 2019 | $18,591 | $12,856 | 
| 2020 | $18,962 | $13,227 | 
| 2021* | $19,341 | $13,609 | 
| 2022* | $19,728 | $14,003 | 
| 2023* | $20,123 | $14,407 | 
| 2024* | $20,525 | $14,824 | 
| 2025* | $20,936 | $15,252 |