| Année | Homme | Femme |
|---|---|---|
| 1990 | 13.8 | 7.5 |
| 1991 | 10.0 | 5.2 |
| 1992 | 9.1 | 4.7 |
| 1993 | 8.2 | 4.0 |
| 1994 | 7.5 | 4.0 |
| 1995 | 6.6 | 3.0 |
| 1996 | 5.7 | 2.6 |
| 1997 | 4.5 | 2.2 |
| 1998 | 4.2 | 2.0 |
| 1999 | 3.5 | 1.7 |
| 2000 | 3.5 | 1.3 |
| 2001 | 2.6 | 1.1 |
| 2002 | 2.6 | 1.1 |
| 2003 | 2.6 | 1.1 |
| 2004 | 3.6 | 1.8 |
| 2005 | 3.0 | 1.4 |
| 2006 | 2.3 | 1.3 |
| 2007 | 2.3 | 1.3 |
| 2008 | 2.2 | 1.2 |