| Year | Count |
|---|---|
| 1988 | 6 |
| 1989 | 6 |
| 1990 | 15 |
| 1991 | 28 |
| 1992 | 15 |
| 1993 | 21 |
| 1994 | 26 |
| 1995 | 24 |
| 1996 | 35 |
| 1997 | 55 |
| 1998 | 61 |
| 1999 | 63 |
| 2000 | 81 |
| 2001 | 90 |
| 2002 | 69 |
| 2003 | 108 |
| 2004 | 213 |
| 2005 | 1,070 |
| 2006 | 992 |
| 2007 | 986 |
| 2008 | 1,840 |
| 2009 | 2,248 |
| 2010 | 1,813 |
| 2011 | 1,818 |
| 2012 | 1,620 |
| 2013 | 1,306 |
| 2014 | 1,027 |
| 2015 | 1,219 |
| 2016 | 1,088 |
| 2017 | 931 |
| 2018 | 702 |
| 2019 | 606 |
| 2020 | 616 |
| 2021 | 901 |
| 2022 | 599 |
| 2023 | 490 |
| 2024 | 392 |