| Sex and Year | Grade | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Total | 9th grade | 10th grade | 11th grade | 12th grade | ||||||
| Percent | S.E. | Percent | S.E. | Percent | S.E. | Percent | S.E. | Percent | S.E. | |
|
Both Sexes
|
||||||||||
| 2009 | 24.2 | 0.8 | 15.3 | 0.8 | 22.3 | 1.3 | 28.3 | 1.5 | 33.5 | 1.3 |
| 2007 | 26.0 | 1.0 | 17.0 | 0.9 | 23.7 | 1.5 | 29.9 | 1.4 | 36.5 | 1.7 |
| 2005 | 25.5 | 1.1 | 19.0 | 1.1 | 24.6 | 1.6 | 27.6 | 1.6 | 32.8 | 1.7 |
| 2003 | 28.3 | 1.0 | 19.8 | 1.2 | 27.4 | 1.5 | 31.8 | 1.5 | 37.2 | 1.2 |
| 2001 | 29.9 | 1.0 | 24.5 | 1.4 | 28.2 | 1.3 | 32.2 | 1.7 | 36.7 | 1.9 |
| 1999 | 31.5 | 1.0 | 21.1 | 1.1 | 32.2 | 1.6 | 34.0 | 1.5 | 41.6 | 2.8 |
| 1997 | 33.4 | 1.1 | 25.7 | 2.0 | 29.9 | 1.9 | 37.5 | 1.5 | 39.3 | 2.4 |
| 1995 | 32.6 | 1.5 | 24.5 | 1.8 | 30.3 | 2.0 | 34.9 | 2.0 | 39.0 | 1.9 |
| 1993 | 30.0 | 1.0 | 22.0 | 1.0 | 26.2 | 1.3 | 31.3 | 1.7 | 39.1 | 1.6 |
| 1991 | 31.3 | 1.7 | 22.6 | 2.0 | 27.1 | 1.8 | 36.3 | 2.5 | 39.3 | 2.7 |
|
Male
|
||||||||||
| 2009 | 25.0 | 1.0 | 13.6 | 1.2 | 23.3 | 1.9 | 30.0 | 1.6 | 36.6 | 2.0 |
| 2007 | 27.8 | 1.4 | 17.0 | 1.7 | 25.5 | 1.9 | 33.1 | 1.3 | 40.4 | 2.6 |
| 2005 | 27.5 | 1.3 | 20.7 | 1.7 | 25.1 | 1.8 | 30.4 | 2.0 | 36.2 | 1.8 |
| 2003 | 29.0 | 1.1 | 18.8 | 1.4 | 27.7 | 1.9 | 34.1 | 2.0 | 39.5 | 1.9 |
| 2001 | 33.5 | 1.5 | 26.2 | 2.1 | 30.1 | 1.8 | 38.5 | 2.3 | 42.0 | 2.1 |
| 1999 | 34.9 | 1.3 | 21.7 | 1.9 | 33.4 | 2.8 | 38.8 | 2.9 | 49.5 | 2.9 |
| 1997 | 37.3 | 1.2 | 25.5 | 2.8 | 32.7 | 1.5 | 45.2 | 2.3 | 44.0 | 2.9 |
| 1995 | 36.2 | 1.5 | 27.6 | 2.6 | 32.1 | 2.3 | 37.8 | 2.4 | 46.5 | 2.1 |
| 1993 | 33.7 | 1.1 | 24.0 | 1.6 | 27.2 | 1.5 | 37.1 | 2.2 | 45.0 | 2.3 |
| 1991 | 36.5 | 2.1 | 24.8 | 2.5 | 31.4 | 2.2 | 44.1 | 3.3 | 45.8 | 3.5 |
|
Female
|
||||||||||
| 2009 | 23.4 | 0.8 | 17.2 | 1.4 | 21.1 | 1.2 | 26.4 | 1.7 | 30.4 | 1.3 |
| 2007 | 24.1 | 1.1 | 17.2 | 1.2 | 21.8 | 1.9 | 26.7 | 2.0 | 32.8 | 1.9 |
| 2005 | 23.5 | 1.2 | 17.3 | 1.4 | 24.1 | 1.8 | 25.0 | 1.7 | 29.2 | 2.0 |
| 2003 | 27.5 | 1.1 | 20.9 | 1.7 | 27.2 | 1.8 | 29.4 | 1.7 | 34.5 | 1.8 |
| 2001 | 26.4 | 1.0 | 23.0 | 1.6 | 26.3 | 1.5 | 26.1 | 1.5 | 31.8 | 2.5 |
| 1999 | 28.1 | 1.0 | 20.2 | 1.6 | 31.1 | 1.8 | 29.0 | 2.5 | 33.9 | 3.0 |
| 1997 | 28.6 | 1.4 | 25.8 | 2.5 | 26.3 | 3.7 | 28.2 | 2.1 | 33.6 | 2.5 |
| 1995 | 28.6 | 2.0 | 20.2 | 1.7 | 28.3 | 2.8 | 31.8 | 2.8 | 31.6 | 2.4 |
| 1993 | 26.0 | 1.1 | 19.7 | 1.6 | 25.3 | 1.6 | 25.1 | 1.4 | 33.0 | 1.8 |
| 1991 | 25.9 | 1.3 | 20.4 | 2.1 | 22.3 | 2.1 | 28.1 | 2.3 | 32.8 | 2.4 |