The chart given shows the changes in proportion of people working in different sectors in two towns in the year of 1960 and 2010.
Overall, town A saw a massive uptick in the amount of workers employed in the service sector from the year 1960 to the 2010. Additionally, during the same years, town B saw a more stable increase in all three sectors which are manufacturing, sales, and services.
The service sector witnessed a 40% increase in the workforce whereas the number of employees involved in sales halved from 30% in 1960 to 16% in 2010. A similar decrease is seen in manufacturing, where a 41% employee base reduced to around 20% by the year 2010.
The manufacturing workforce in town B reduced to 53% in 2010 from 70% in 1960. Surprisingly, sales sluggishly grew from 20% to a 22% in 2010. Whereas services sector welcomed 10% more employees.