DemographicsCasey is approximately 2.62 square kilometres. In 2016 the population of Casey was 5758. The population is 49% male and 51% female. On average the monthly mortgage repayments in Casey are $1800 to $2399. The most common weekly income bracket is $1250 to $1499 per week. Weekly rents in the area are on average $350 to $449.