| Residency | Year | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1999 | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | |
| Total | 230 | 254 | 326 | 343 | 447 | 662 | 899 | 879 | 886 | 999 |
| U.S. Resident | 229 | 251 | 322 | 340 | 445 | 661 | 896 | 877 | 882 | 997 |
| Nonresident Alien | 1 | 2 | 3 | 3 | 2 | 1 | 3 | 2 | 4 | 2 |
| Unknown | - | 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 | 99.6% | 98.8% | 98.8% | 99.1% | 99.6% | 99.8% | 99.7% | 99.8% | 99.5% | 99.8% |
| Nonresident Alien | 0.4% | 0.8% | 0.9% | 0.9% | 0.4% | 0.2% | 0.3% | 0.2% | 0.5% | 0.2% |
| Unknown | - | 0.4% | 0.3% | - | - | - | - | - | - | - |