Year All common birds (168 species) Common farmland birds (39 species) Common forest birds (34 species)
1990 100 100 100
1991 100.16 98.71 100.49
1992 100.26 97.46 100.74
1993 100.39 96.41 100.82
1994 100.48 95.41 100.78
1995 100.49 94.36 100.64
1996 100.36 93.11 100.45
1997 99.98 91.59 99.97
1998 99.41 89.87 99.07
1999 99.34 88.06 97.96
2000 97.72 86.25 96.83
2001 96.95 84.57 95.88
2002 96.34 83.09 95.28
2003 95.83 81.73 94.93
2004 95.32 80.42 94.66
2005 94.84 79.18 94.48
2006 94.41 78.4 94.42
2007 94.06 77.06 94.52
2008 93.8 76.2 94.75
2009 93.57 75.41 95.11
2010 93.38 74.71 95.58
2011 93.24 74.09 96.17
2012 93.15 73.56 96.87
2013 93.09 73.11 97.7
2014 93.08 72.75 98.65
2015 93.13 72.48 99.74
2016 93.21 72.27 100.95
2017 93.33 72.14 102.32
2018 93.45 72.01 103.71
2019 93.57 71.88 105.12