Table 228.40.

Percentage of students in grades 9-12 who reported being threatened or injured with a weapon on school property during the previous 12 months, by selected student characteristics and number of times threatened or injured: Selected years, 1993 through 2011

[Standard errors appear in parentheses]
Number of times and year	Total			Sex						Race/ethnicity1																					Grade
				Male			Female			White			Black			Hispanic			Asian2			American Indian/ Alaska Native			Pacific Islander2			Two or more races2			9th grade			10th grade			11th grade			12th grade
1	2			3			4			5			6			7			8			9			10			11			12			13			14			15
At least once
1993	7.3		(0.44)	9.2		(0.64)	5.4		(0.40)	6.3		(0.58)	11.2		(0.95)	8.6		(0.83)	—		(†)	11.7		(2.50)	—		(†)	—		(†)	9.4		(0.92)	7.3		(0.59)	7.3		(0.64)	5.5		(0.62)
1995	8.4		(0.52)	10.9		(0.57)	5.8		(0.68)	7.0		(0.53)	11.0		(1.61)	12.4		(1.44)	—		(†)	11.4	!	(4.22)	—		(†)	—		(†)	9.6		(0.96)	9.6		(1.03)	7.7		(0.64)	6.7		(0.57)
1997	7.4		(0.45)	10.2		(0.71)	4.0		(0.32)	6.2		(0.56)	9.9		(0.91)	9.0		(0.63)	—		(†)	12.5	!	(5.15)	—		(†)	—		(†)	10.1		(1.02)	7.9		(1.14)	5.9		(0.70)	5.8		(0.80)
1999	7.7		(0.42)	9.5		(0.80)	5.8		(0.64)	6.6		(0.35)	7.6		(0.85)	9.8		(1.09)	7.7		(1.05)	13.2	!	(5.45)	15.6		(4.46)	9.3		(1.22)	10.5		(0.95)	8.2		(0.92)	6.1		(0.46)	5.1		(0.79)
2001	8.9		(0.55)	11.5		(0.66)	6.5		(0.52)	8.5		(0.66)	9.3		(0.71)	8.9		(1.05)	11.3		(2.73)	15.2	!	(4.57)	24.8		(7.16)	10.3		(2.33)	12.7		(0.89)	9.1		(0.75)	6.9		(0.65)	5.3		(0.52)
2003	9.2		(0.75)	11.6		(0.96)	6.5		(0.61)	7.8		(0.77)	10.9		(0.80)	9.4		(1.23)	11.5		(2.66)	22.1		(4.79)	16.3		(4.31)	18.7		(3.11)	12.1		(1.25)	9.2		(1.02)	7.3		(0.69)	6.3		(0.92)
2005	7.9		(0.35)	9.7		(0.42)	6.1		(0.41)	7.2		(0.46)	8.1		(0.69)	9.8		(0.86)	4.6		(1.10)	9.8		(2.67)	14.5	!	(4.93)	10.7		(2.33)	10.5		(0.63)	8.8		(0.72)	5.5		(0.43)	5.8		(0.52)
2007	7.8		(0.44)	10.2		(0.59)	5.4		(0.41)	6.9		(0.52)	9.7		(0.86)	8.7		(0.60)	7.6	!	(2.29)	5.9		(1.24)	8.1	!	(2.45)	13.3		(2.25)	9.2		(0.69)	8.4		(0.51)	6.8		(0.57)	6.3		(0.64)
2009	7.7		(0.37)	9.6		(0.59)	5.5		(0.37)	6.4		(0.43)	9.4		(0.80)	9.1		(0.61)	5.5		(0.91)	16.5		(2.68)	12.5		(3.11)	9.2		(1.50)	8.7		(0.53)	8.4		(0.72)	7.9		(0.60)	5.2		(0.53)
2011	7.4		(0.31)	9.5		(0.39)	5.2		(0.37)	6.1		(0.35)	8.9		(0.64)	9.2		(0.81)	7.0		(0.99)	8.2		(1.52)	11.3		(3.23)	9.9		(1.35)	8.3		(0.63)	7.7		(0.58)	7.3		(0.61)	5.9		(0.45)
Number of times, 2011
0 times	92.6		(0.31)	90.5		(0.39)	94.8		(0.37)	93.9		(0.35)	91.1		(0.64)	90.8		(0.81)	93.0		(0.99)	91.8		(1.52)	88.7		(3.23)	90.1		(1.35)	91.7		(0.63)	92.3		(0.58)	92.7		(0.61)	94.1		(0.45)
1 time	3.1		(0.17)	3.6		(0.26)	2.5		(0.22)	2.9		(0.25)	3.6		(0.40)	3.1		(0.32)	2.7	!	(0.88)	3.7		(0.92)	2.5	!	(1.10)	3.9		(1.08)	4.1		(0.53)	2.5		(0.36)	3.0		(0.33)	2.5		(0.28)
2 or 3 times	1.9		(0.15)	2.6		(0.25)	1.3		(0.18)	1.5		(0.17)	2.3		(0.35)	2.8		(0.35)	2.0	!	(0.64)	2.8		(0.60)	‡		(†)	2.3		(0.67)	2.1		(0.24)	2.5		(0.33)	1.8		(0.29)	1.3		(0.21)
4 to 11 times	1.4		(0.13)	1.8		(0.20)	1.0		(0.15)	1.1		(0.15)	1.9		(0.39)	1.9		(0.37)	‡		(†)	‡		(†)	‡		(†)	0.8	!	(0.34)	1.2		(0.24)	1.7		(0.24)	1.3		(0.24)	1.2		(0.22)
12 or more times	1.0		(0.12)	1.5		(0.19)	0.4		(0.09)	0.7		(0.10)	1.1		(0.23)	1.4		(0.32)	‡		(†)	‡		(†)	‡		(†)	2.8	!	(0.96)	0.9		(0.20)	0.9		(0.22)	1.2		(0.24)	0.8		(0.21)

—Not available.

†Not applicable.

!Interpret data with caution. The coefficient of variation (CV) for this estimate is between 30 and 50 percent.

‡Reporting standards not met. Either there are too few cases for a reliable estimate or the coefficient of variation (CV) is 50 percent or greater.

1 Race categories exclude persons of Hispanic ethnicity.

2 Before 1999, Asian students and Pacific Islander students were not categorized separately, and students were not given the option of choosing two or more races. Because the response categories changed in 1999, caution should be used in comparing data on race from 1993, 1995, and 1997 with data from later years.

NOTE: "On school property" was not defined for survey respondents. "Weapon" was defined as a gun, knife, or club for survey respondents. Detail may not sum to totals because of rounding.

SOURCE: Centers for Disease Control and Prevention, Division of Adolescent and School Health, Youth Risk Behavior Surveillance System (YRBSS), 1993 through 2011. (This table was prepared September 2013.)