On each horizontal line in the figure below, the five large dots indicate the populations of cities A, B, C, D and E in the year indicated. Which city had the greatest percentage increase in population from 1970 to 1980?
Note: Population in Thousands
(Source: Adaped from The Contest Problem Book V, American High Schol Mathematics Examinations and American Invitational Mathematics Examinations, 1983-1988)
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