"According to the Gallup Poll, 24 percent of American adults exercised regularly in 1961, and 50 percent after 1968. The peak was 59 percent in 1984, dropping off to 51 percent last September"

This quote by Kenneth H. Cooper is referring to the outcomes of the Gallup Poll, which evaluated American grownups on their exercise practices. The outcomes show that in 1961, just 24 percent of American grownups exercised frequently. Nevertheless, after 1968, the portion of adults who worked out consistently increased to 50 percent. The height of 59 percent was seen in 1984, but after that left to 51 percent in September of last year. This quote shows that although the percentage of grownups that work out frequently has increased for many years, it has actually not been a consistent rise. The percent of grownups that exercise on a regular basis has actually fluctuated for many years, with the greatest percent being seen in 1984.