| Year | Total Expenses | Average Net Price | 
|---|---|---|
| 2015 | $25,920 | $21,991 | 
| 2016 | $26,527 | $22,458 | 
| 2017 | $22,804 | $18,704 | 
| 2018 | $22,804 | $18,603 | 
| 2019 | $22,313 | $17,960 | 
| 2020 | $22,476 | $18,123 | 
| 2021* | $22,476 | $18,025 | 
| 2022* | $22,476 | $17,928 | 
| 2023* | $22,476 | $17,831 | 
| 2024* | $22,476 | $17,735 | 
| 2025* | $22,476 | $17,639 |