Every year, a survey of 1000 people is conducted by the Health Organization (HO). HO found that in the year 2011, 2012, 2013, 2014 and 2015 the percentage of people affected by Dengue were 30%, 40%, 30%, 20% and 45% respectively. HO also found that every year out of the affected people 60% were students, 10% were house-wives and 30% were teachers. The number of housewives, students and teachers were in the ratio 20 : 11 : 9 each year.