Computational Formulas Template printable pdf download

Computational

Formulas

CRIMES

Crime rate – A crime rate describes the number of crimes reported to law enforcement agencies

for every 100,000 persons within a population. A crime rate is calculated by dividing the number of

reported crimes by the total population. The result is then multiplied by 100,000. For example, in 2014

there were 48,650 robberies in California and the population was 38,499,378. This equals a robbery

crime rate of 126.4 per 100,000.

48,650

= 0.0012636 x 100,000 = 126.4

38,499,378

Clearance rate – A clearance rate describes the percentage of clearances reported to the number of

crimes reported. A clearance rate is calculated by dividing the number of clearances by the number of

crimes reported. The result is multiplied by 100. For example, in 2014 there were 1,091 clearances for

homicide crimes and 1,697 homicides reported. This equals a homicide clearance rate of 64.3 percent.

1,091

= 0.64289 x 100 = 64.3 percent

1,697

ARRESTS

Arrest rate – An arrest rate describes the number of arrests made by law enforcement agencies per

100,000 total population or per 100,000 population considered to be at risk for arrest. Regardless of

the population used, both rates are calculated in the same manner. An arrest rate is calculated by

dividing the number of reported arrests by the desired population. The result is multiplied by 100,000.

For example: 1) In 2014, there were 439,958 total felony arrests and the total population was

38,499,378, which equates to a 1,142.8 arrest rate; 2) In 2014, there were 439,958 total felony arrests

and the population at risk (10-69 years of age) was 30,190,364, which equates to a 1,457.3 arrest rate.

439,958

= 0.0114276 x 100,000 = 1,142.8 per 100,000 population

38,499,378

439,958

= 0.0145727 x 100,000 = 1,457.3 per 100,000 population at risk

30,190,364

Computational Formulas Template