Within a population of 1500 elderly adults, an initial clini…

Within а pоpulаtiоn оf 1500 elderly аdults, an initial clinical examination identifies 87 individuals with COPD. Over the following 10 years, 37 additional people develop COPD; four of these individuals die of COPD within 1 day of their diagnosis (no one is diagnosed on the last day of the study). Of the originally identified individuals, 8 die of COPD over the same time period and 23 people without COPD die of other causes. What is the case fatality rate of COPD?