| Year | Count |
|---|---|
| 1987 | 6 |
| 1989 | 5 |
| 1993 | 12 |
| 1994 | 17 |
| 1995 | 17 |
| 1996 | 13 |
| 1997 | 27 |
| 1998 | 24 |
| 1999 | 45 |
| 2000 | 42 |
| 2001 | 86 |
| 2002 | 68 |
| 2003 | 75 |
| 2004 | 96 |
| 2005 | 196 |
| 2006 | 277 |
| 2007 | 346 |
| 2008 | 423 |
| 2009 | 621 |
| 2010 | 609 |
| 2011 | 773 |
| 2012 | 1,037 |
| 2013 | 1,118 |
| 2014 | 1,035 |
| 2015 | 1,207 |
| 2016 | 1,310 |
| 2017 | 1,090 |
| 2018 | 1,105 |
| 2019 | 1,241 |
| 2020 | 948 |
| 2021 | 1,002 |
| 2022 | 790 |
| 2023 | 710 |
| 2024 | 591 |