| 2000 | 2005 | 2010 | 2011 | |
|---|---|---|---|---|
| Nordrhein-Westfalen | 5 090 | 6 897 | 7 625 | 7 129 |
| Hessen | 850 | 1 142 | 1 257 | 1 953 |
| Niedersachsen | 2 090 | 1 757 | 1 346 | 1 547 |
| Rheinland-Pfalz | 516 | 713 | 785 | |
| Schleswig-Holstein | 431 | 393 | 538 | 651 |
| Hamburg | 256 | 262 | 547 | 460 |
| Sachsen-Anhalt | 610 | 572 | 453 | 366 |
| Baden-Württemberg | 211 | 286 | 313 | 310 |
| Mecklenburg-Vorpommern | 403 | 271 | 328 | 294 |
| Saarland | 118 | 83 | 102 | 109 |
| Bremen | 19 | 131 | 11 | 23 |
| Bayern | 42 | 48 | 36 | 12 |
| Brandenburg | 80 | 49 | 42 |