| Year | Frequency | Percentage |
| 2010 | 48 | 24.6 |
| 2011 | 38 | 19.5 |
| 2012 | 31 | 15.9 |
| 2013 | 35 | 17.9 |
| 2014 | 22 | 11.3 |
| 2016 | 6 | 3.1 |
| 2017 | 11 | 5.6 |
| 2018 | 3 | 1.5 |
| 2019 | 1 | 0.5 |
| Total | 195 | 100.0 |