An NGO is implementing a program to improve health by combating malaria. Because the NGO is trying to help the neediest, it targets the poorest people in a village. To identify poor people, the NGO visits households and decides a household is "poor" if the roof of the house is made of a semi- permanent material like thatch, and the household is considered "not poor" if the roof is made of a permanent material like iron sheets. In the villages the NGO works in, 500 house- holds are classified as poor and 2,000 are not poor. The NGO gives each poor household 2 insecticide-treated bednets and also gives them access to effective anti-malarials called ACT (artemisinin combination therapies). If anybody in the household thinks they are getting malaria, they can go to the local clinic and get tested, and if they are positive they get ACT for free. The NGO is interested in knowing whether the program works, and hires you as a consultant to evaluate the program. The NGO has some data available - before and after the program, the NGO had tested every individual in the village for malaria. The average malaria rates are as follows