2. Relative increase is the actual diffecence between the two census counts expressed in percent relative to the population size made during ao earlier census. Relative Increase = where: Pt = population size at a later tlrne Po = population size at an earlier time population Composition Pt Po Po The composition of the population is commonly described in terms of its age and sex. The nurse utilizes data on age and sex composition to decide who among the population groups merits attention in terms of health services,md programs. 1. Sex compositio n To describe the sex composition of the population, the nurse computes for (he sex ratio. The sex ratio compares the number of males to the number of females in the population using the formula below. number of males Sex Ratio =---------X 100 number of femafes The sex rntio represents the number of males for every 100 females in the population. 2. Age composition There are two ways to describe tbe age composition of the population. a. Median age divides the populatio n into two equal par~. So, if the median age is said to be 19 years old, it means half of the population belongs to 19 years and above, while the other half belongs to ages below 19 years old. b. Dependen cy Ratio compares the number of economically dependent with the economically productive group in the population. The economically dependent are those who belong to the o-14 and 65 and,1lxwe age groups. Considered to be econornicnlly productive are those "ithin the 15 to 64 age group. The dependency ratio represents the number of economically dependent for every 100 economically productive. Dependency Ratio = total populat!Ofl of the o-14 and 65 and above a_ge group--·-----------x100 total po PUlation of 15-64 age sroup 181 