| Year | Total Expenses | Average Net Price |
|---|---|---|
| 2015 | $18,714 | $13,430 |
| 2016 | $19,838 | $14,923 |
| 2017 | $20,429 | $15,264 |
| 2018 | $20,429 | $12,419 |
| 2019 | $20,447 | $11,221 |
| 2020 | $20,602 | $11,376 |
| 2021* | $20,759 | $11,533 |
| 2022* | $20,916 | $11,692 |
| 2023* | $21,075 | $11,853 |
| 2024* | $21,235 | $12,017 |
| 2025* | $21,397 | $12,183 |