Gather all of the information for the two variables you are comparing. In the case of a comparison of the economics of an industry, you will need the national data for the change in a region and change in regional economics overall.
Use the formula to calculate shift share that equals the total Industry Employment divided by the local industry employment minus the industry growth minus one:
Industry Employment / Local Industry Employment - Industry Growth - 1 = Shift Share
Determine the components of each variable in the equation. We can assume the total industry has 100,000 employees and the local has 80,000 and the industry growth rate is 15 percent.
Calculate according to assumptions or data acquired.
100,000 / 80,000 - .15 - 1 = .1
The shift share is 10 percent (.1)