Of 3,143 counties in the United States in 2013, Fayette County ranked 2,882 in the longevity of male residents and 3,091 of female residents.  Males in Fayette County lived an average of 71.2 years and females lived an average of 75.3 years compared to the national average for longevity of 76.5 for males and 81.2 for females. The average longevity of men in Fayette County increased by 2.0 years from 1985 to 2013 compared to a national average for the same period of an increased life span for men of 5.5 years.  The average longevity, however, for females in Fayette County declined by 4.2 years between 1985 and 2013 compared to the national average for the same period of an increased life span of 3.1 years for women. High rates of smoking and obesity and a low rate of physical activity appear to be contributing factors to the low level of longevity for both sexes.
Question: How many years did it take the male national average to increase by 5.5 years?
Answer: 28