Zobrazení grafu: týden | měsíc | půl roku | rok | 5 let | 15 let
| Rok | Maximální | Minimální | Průměr |
|---|---|---|---|
| 1991 | 5.020 | 4.750 | 4.877 |
| 1992 | 5.230 | 4.055 | 4.879 |
| 1993 | 4.102 | 3.509 | 3.754 |
| 1994 | 3.871 | 3.547 | 3.728 |
| 1995 | 4.103 | 3.473 | 3.724 |
| 1996 | 4.195 | 3.870 | 4.049 |
| 1997 | 4.524 | 3.743 | 4.151 |
| 1998 | 4.471 | 3.629 | 4.062 |
| 1999 | 4.334 | 3.691 | 4.182 |
| 2000 | 4.516 | 3.934 | 4.219 |
| 2001 | 3.994 | 3.324 | 3.686 |
| 2002 | 3.527 | 3.136 | 3.363 |
| 2003 | 3.613 | 3.392 | 3.491 |
| 2004 | 3.650 | 3.372 | 3.496 |
| 2005 | 3.380 | 3.036 | 3.210 |
| 2006 | 3.110 | 2.991 | 3.063 |
| 2007 | 3.131 | 2.760 | 3.001 |
| 2008 | 2.820 | 2.381 | 2.599 |
| 2009 | 2.684 | 2.348 | 2.486 |
| 2010 | 2.823 | 2.540 | 2.651 |
| 2011 | 2.897 | 2.601 | 2.724 |
| 2012 | 2.933 | 2.827 | 2.877 |