| Bestand | ||||
| publish | archive | Jahresende | Veränderung | |
| 2002 | 1 | 0 | 1 | 1 |
| 2003 | 0 | 0 | 1 | 0 |
| 2004 | 2 | 0 | 3 | 2 |
| 2005 | 12 | 7 | 8 | 5 |
| 2006 | 9 | 5 | 12 | 4 |
| 2007 | 15 | 6 | 21 | 9 |
| 2008 | 16 | 6 | 31 | 10 |
| 2009 | 27 | 14 | 44 | 13 |
| 2010 | 38 | 16 | 66 | 22 |
| 2011 | 48 | 25 | 89 | 23 |
| 2012 | 37 | 18 | 108 | 19 |
| 2013 | 61 | 19 | 150 | 42 |
| 2014 | 36 | 42 | 144 | -6 |
| 2015 | 12 | 26 | 130 | -14 |
| 2016 | 33 | 30 | 133 | 3 |
| 2017 | 12 | 17 | 128 | -5 |
| 2018 | 37 | 18 | 147 | 19 |
| 2019 | 28 | 18 | 157 | 10 |
| 2020 | 36 | 27 | 166 | 9 |
| 2021 | 32 | 7 | 191 | 25 |
| gesamt | 492 | 301 |
Stand 02.05.2021