Assume the world catch of fish in 1950 was 12 million tons and in 1955 it was 96 million tons. Find the average rate of change from 1950 to 1995.
+36916 It changed 96-12 = 84 million tons in 5 years of increase ( 51 52 53 54 55 )
84/5 =16.8 million tons a year increase
The second part of your question has different dates 1950 to 1995 is 45 years of increase
84/45 = 1.867 million tons/yr increase average
