| Residency | Year | |||||||||
| 1994 | 1995 | 1996 | 1997 | 1998 | 1999 | 2000 | 2001 | 2002 | 2003 | |
| Total | 164 | 181 | 201 | 221 | 272 | 246 | 312 | 383 | 403 | 452 |
| U.S. Resident | 160 | 177 | 196 | 215 | 266 | 242 | 308 | 381 | 401 | 450 |
| Nonresident Alien | 1 | - | 1 | - | - | - | 2 | 1 | 1 | 1 |
| Unknown | 3 | 4 | 4 | 6 | 6 | 4 | 2 | 1 | 1 | 1 |
| Total (%) | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% |
| U.S. Resident | 97.6% | 97.8% | 97.5% | 97.3% | 97.8% | 98.4% | 98.7% | 99.5% | 99.5% | 99.6% |
| Nonresident Alien | 0.6% | - | 0.5% | - | - | - | 0.6% | 0.3% | 0.2% | 0.2% |
| Unknown | 1.8% | 2.2% | 2.0% | 2.7% | 2.2% | 1.6% | 0.6% | 0.3% | 0.2% | 0.2% |