Apple Macs now account for 8% of computer market.
In a survey conducted by Net Applications on 40,000 sites, the results show that more than 8% of computers accessing the web were using Apple Macs. These numbers are only indicative of Macs that are used to access the internet. 8% may seem like a small number, but consider that the current estimated internet usage statistics pin a number around 1463632361 users. That places Macs used to access the internet around 117090588 machines.
These numbers only highlight the importance of testing Apple Mac as a platform against your external facing websites.