| 1990 |
8 songs
|
|
| 1991 |
7.5 songs
|
|
| 1992 |
10.7 songs
|
|
| 1993 |
16.1 songs
|
|
| 1994 |
18.8 songs
|
|
| 1995 |
23.8 songs
|
|
| 1996 |
23.1 songs
|
|
| 1997 |
12.8 songs
|
|
| 1998 |
21.9 songs
|
|
| 1999 |
7 songs
|
|
| 2000 |
25.5 songs
|
|
| 2001 |
10.3 songs
|
|
| 2002 |
14.6 songs
|
|
| 2003 |
26.4 songs
|
|
| 2004 |
15.7 songs
|
|
| 2005 |
25.6 songs
|
|
| 2006 |
25.1 songs
|
|
| 2007 |
22.3 songs
|
|
| 2008 |
26.6 songs
|
|
| 2009 |
27.3 songs
|
|
| 2010 |
23.3 songs
|
|
| 2011 |
27.4 songs
|
|
| 2012 |
27.4 songs
|
|
| 2013 |
30.9 songs
|
|
| 2014 |
29 songs
|
|
| 2015 |
26.7 songs
|
|
| 2016 |
31.1 songs
|
|
| 2017 |
25.6 songs
|
|
| 2018 |
26.6 songs
|