| Residency | Year | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1998 | 1999 | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | |
| Total | 1,785 | 1,879 | 2,177 | 3,005 | 3,663 | 4,270 | 4,201 | 4,152 | 4,141 | 4,225 |
| U.S. Resident | 1,750 | 1,845 | 2,112 | 2,928 | 3,561 | 4,146 | 4,082 | 4,046 | 4,046 | 4,144 |
| Nonresident Alien | 25 | 26 | 34 | 44 | 71 | 97 | 98 | 87 | 86 | 73 |
| Unknown | 10 | 8 | 31 | 33 | 31 | 27 | 21 | 19 | 9 | 8 |
| Total (%) | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% |
| U.S. Resident | 98.0% | 98.2% | 97.0% | 97.4% | 97.2% | 97.1% | 97.2% | 97.4% | 97.7% | 98.1% |
| Nonresident Alien | 1.4% | 1.4% | 1.6% | 1.5% | 1.9% | 2.3% | 2.3% | 2.1% | 2.1% | 1.7% |
| Unknown | 0.6% | 0.4% | 1.4% | 1.1% | 0.8% | 0.6% | 0.5% | 0.5% | 0.2% | 0.2% |