Usage share of operating systems computer's installed base statistics, and actual (web) use needs not follow installed base. Also, Microsoft includes tablets (but StatCounter may also for Windows, while it wouldn't for e.g. Android). Video game store Steam publishes a monthly "Hardware & Software Survey", with the statistics below: By Q1 2018, mobile operating systems that can be found on smartphones, include Google's dominant Android (and variants) and Apple's iOS, with both combined at almost 100% market share. According to research by InsightPortal, there is a clear correlation between the GDP per capita of a country and that country's respective smartphone OS market share, Showing
Market share share is closely monitored for signs of change in the competitive landscape, and it frequently drives strategic or tactical action." Increasing market share is one of the most important objectives of business. The main advantage of using market share as a measure of business performance is that it is less dependent upon macro environmental variables such as the state of the economy or changes in tax policy. In the United States market, however, increasing market share may be dangerous for makers of fungible and potentially hazardous products such as medicine, due to a US-only legal doctrine called market share liability.