| 1992 | 2000 | 2002 | 2004 | 2006 | 2008 | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Region | M | SD | M | SD | M | SD | M | SD | M | SD | M | SD |
Northeast | 39.6 | 22.36 | 49.39 | 22.60 | 50.79 | 22.0 | 49.78 | 19.25 | 50.30 | 19.43 | 50.13 | 21.39 |
Midwest | 69.1 | 11.84 | 69.62 | 9.32 | 72.51 | 10.77 | 73.25 | 10.69 | 72.87 | 10.78 | 70.17 | 13.11 |
South | 69.0 | 15.11 | 67.80 | 16.17 | 71.68 | 14.74 | 74.82 | 15.11 | 74.37 | 15.85 | 73.37 | 17.51 |
West | 31.7 | 22.78 | 34.13 | 20.70 | 37.26 | 20.86 | 39.90 | 19.5 | 41.16 | 19.35 | 43.65 | 19.78 |