Zobrazení grafu: týden | měsíc | půl roku | rok | 5 let | 15 let
| Rok | Maximální | Minimální | Průměr |
|---|---|---|---|
| 1993 | 16.719 | 15.387 | 16.103 |
| 1994 | 18.193 | 16.495 | 17.065 |
| 1995 | 18.036 | 16.647 | 17.414 |
| 1996 | 19.519 | 17.379 | 18.666 |
| 1997 | 23.011 | 18.942 | 20.953 |
| 1998 | 20.934 | 14.822 | 17.368 |
| 1999 | 19.879 | 15.756 | 18.301 |
| 2000 | 20.050 | 15.902 | 17.601 |
| 2001 | 16.991 | 14.542 | 15.994 |
| 2002 | 15.942 | 14.105 | 15.140 |
| 2003 | 17.454 | 15.278 | 16.388 |
| 2004 | 18.209 | 15.939 | 17.040 |
| 2005 | 17.662 | 16.036 | 16.863 |
| 2006 | 16.797 | 13.454 | 14.668 |
| 2007 | 16.546 | 13.580 | 14.921 |
| 2008 | 13.990 | 10.613 | 12.080 |
| 2009 | 13.361 | 10.667 | 11.997 |
| 2010 | 14.881 | 13.022 | 13.761 |
| 2011 | 15.415 | 12.547 | 13.989 |
| 2012 | 16.133 | 15.089 | 15.553 |