| 1978 |
| 1980 |
| 1985 |
| 1989 |
| 1990 |
| 1991 |
| 1992 |
| 1993 |
| 1994 |
| 1995 |
| 1996 |
| 1997 |
| 1998 |
| 1999 |
| 2000 |
| 2001 |
| 2002 |
| 2003 |
| 2004 | |
| 27.45 |
123.72 |
22.2 |
| 31.13 |
179.68 |
17.3 |
| 58.25 |
427.5 |
13.6 |
| 98.21 |
843.72 |
11.6 |
| 101.59 |
897.99 |
11.3 |
| 108.94 |
1081.75 |
10.1 |
| 118.36 |
1365.06 |
8.7 |
| 166.64 |
1909.49 |
8.7 |
| 209.39 |
2666.86 |
7.9 |
| 248.5 |
3524.79 |
7.1 |
| 291.75 |
4146.06 |
7 |
| 340.52 |
4638.24 |
7.3 |
| 401.8 |
4987.5 |
8.1 |
| 477.4 |
5364.89 |
8.9 |
| 658.42 |
6036.34 |
10.9 |
| 917.76 |
6748.15 |
13.6 |
| 1166.58 |
7796 |
15 |
| 1468.89 |
9395 |
15.6 |
| 1805.16 |
11243 |
16.1 | |
