The line graph shows the change in the populations of Yamhill, Columbia and Washington, counties in Oregon, from 1940 to 2000.
Overall, it can be seen from the graph that the populations of all three counties increased over the period but most significantly in Washington.
According to the graph there was a similar trend in population growth in Yamhill and Columbia between 1940 and 1970, both rising by about 10,000 residents. The population in Columbia rose to approximately 25,000 while Yamhill increased to just under 35,000 residents. However, the population in Washington rose steadily from 75,000 to almost 120,000 people.
Over the next thirty years the populations in all three counties more than doubled. Steady growth was seen in both Yamhill and Columbia, by 2000 the population in Columbia had increased to just over 75,000 while in Yamhill the figure was around 90,000. A significant increase can be seen for the population of Washington rising to over 240,000 residents by the year 2000.
