| Year | Visitors |
|---|---|
| 2019 | 419,585 |
| 2018 | 410,893 |
| 2017 | 413,151 |
| 2016 | 414,170 |
| 2015 | 412,377 |
| 2014 | 408,641 |
| 2013 | 386,084 |
| 2012 | 404,248 |
| 2011 | 379,906 |
| 2010 | 333,463 |
| 2009 | 298,519 |
| 2008 | 280,279 |
| 2007 | 265,459 |
| 2006 | 255,060 |
| 2005 | 327,921 |
| 2004 | 236,353 |
| 2003 | 227,200 |
| 2002 | 299,958 |
| 2001 | 390,130 |
| 2000 | 393,175 |
| 1999 | 391,235 |
| 1998 | 384,331 |
| 1997 | 365,843 |
| 1996 | 345,739 |
| 1995 | 358,029 |
| 1994 | 467,858 |
| 1993 | 328,256 |
| 1992 | 341,487 |
| 1991 | 232,064 |
| 1990 | 194,531 |
| 1989 | 102,779 |