Final answer:
Sales volume and market share measure market performance, and alternatives like the four-firm concentration ratio and Herfindahl-Hirschman Index (HHI) assess market competitiveness. GDP per worker is another broader metric for productivity.
Step-by-step explanation:
Sales volume and market share are the most popular measures of market performance. There are indeed other methods to measure productivity beyond the amount produced per hour of work. Productivity can be viewed through various lenses, such as the four-firm concentration ratio and the Herfindahl-Hirschman Index (HHI), both of which gauge the competitiveness within a market.
The four-firm concentration ratio is determined by summing up the market shares of the top four firms in a given market. The HHI, on the other hand, is calculated by summing the squares of all firms' market shares within a market. Moreover, productivity can also be measured using GDP per worker, which links the output to the labor input and offers a broader macroeconomic perspective.