Answer:
3,500,000/ 13
It means every 13 years it grows 3,500,000.
Explanation:
The slope is a ration of the vertical distance to the horizontal distance between any two points on the line. This means count the up and down distance and the left and right distance between two points.
Find two points on the line that cross through the grid line intersections like here (200, 500,000) and (2013, 4,000000).
The vertical distance is 4,000,000 - 500,000 = 3,500,000.
The horizontal distance is 2013-2000 = 13.
Write a ratio or fraction between the two distances.
3,500,000/ 13
It means every 13 years it grows 3,500,000.