Wednesday, June 11, 2014

Economic Diversity: Further Analysis of the Hachman Index

Tyson Smith, Regional Economist

In the summer issue of Local Insights we explored local area industry diversity using the Hachman Index. As stated in the article, many economists believe that economic diversification promotes stability in local markets. The article also touches on the difficulty of identifying an exact index value that denotes an appropriately diverse economy. One way to examine Hachman Index values is described below:

“It is difficult to determine exactly what index value constitutes a highly diversified region when there are large differences in total employment [among the regions]. However, if a county’s Hachman Index ranks considerably higher than its total employment count – relative to the other counties in the state – that is an indication that the county is relatively diverse. Using this method reveals that Morgan County had the eighteenth highest Hachman Index and the 25th largest employment base in the state, making it more diverse than counties of similar size. Both Davis and Weber’s index values ranked similarly to their total employment ranks of third and fourth, respectively.”

This simple comparative method highlights the correlation between the size of the workforce in a given county and the industrial diversity in that area. In general, counties with larger populations do not rely on one or two key industries for employment. On the other hand, small communities in less populous counties often exist because their region has (or had) a comparative advantage in a single industry. The relationship between employment count and economic diversity allows us to identify counties that are more or less diverse[1] than expected using the matching exercise in the chart to the right.

[1] Counties where the Hachman Index ranks more than two spots higher or lower than the Total Employment ranking are identified as “More Diverse” or “Less Diverse”, respectively. The "two spot" difference as a means of identifying notable incongruities does not represent a scientific methodology, it is only meant to give directional insight into the data.