| Year | Count |
|---|---|
| 1991 | 13 |
| 1992 | 12 |
| 1993 | 21 |
| 1994 | 28 |
| 1995 | 42 |
| 1996 | 42 |
| 1997 | 97 |
| 1998 | 221 |
| 1999 | 379 |
| 2000 | 545 |
| 2001 | 726 |
| 2002 | 975 |
| 2003 | 1,348 |
| 2004 | 6 |
| 2004 | 1,570 |
| 2005 | 1,783 |
| 2006 | 2,203 |
| 2007 | 5 |
| 2007 | 2,467 |
| 2008 | 3,087 |
| 2009 | 4,110 |
| 2010 | 4,554 |
| 2011 | 5,631 |
| 2012 | 14 |
| 2012 | 7,953 |
| 2013 | 9,421 |
| 2014 | 9,010 |
| 2015 | 11,110 |
| 2016 | 11,307 |
| 2017 | 10,930 |
| 2018 | 10,182 |
| 2019 | 9,387 |
| 2020 | 6,412 |
| 2021 | 6,941 |
| 2022 | 5,632 |
| 2023 | 4,373 |
| 2024 | 4,055 |