1993-1996 | 1997-2001 | 2002-2006 | 2007-2011 | 2012-2014 | |
---|---|---|---|---|---|
Northeast | 4.19 [4.02 – 4.38] | 4.90 [4.69 – 5.19] | 5.45 [5.01 –6.04] | 6.71 [6.30 – 7.24] | 6.89 [6.39 – 7.30] |
Midwest | 4.43 [4.23 – 4.56] | 5.29 [5.00 – 5.58] | 5.38 [5.18 – 5.55] | 6.92 [6.41 – 7.59] | 7.72 [7.54 – 7.82] |
South | 4.54 [4.27 – 4.44] | 5.57 [5.25 – 6.04] | 5.70 [5.38 – 6.02] | 6.85 [6.01 –7.56] | 7.64 [7.16 – 7.95] |
West | 4.25 [3.87 – 4.53] | 5.25 [4.92 – 5.69] | 5.87 [5.49 – 6.22] | 7.12 [6.63 –7.64] | 7.81 [7.52 – 8.17] |
All Regions, All Years | 6.11 [3.18 - 9.37] |