The Web Standards Group recommends that webpages be designed to work with the browsers and platforms that approximately 90% of your website’s visitors use.
Website maintainers should use web analytics tools to analyze traffic statistics for their site.
As of June 2015, UCSB policy allows the use of Google Analytics for tracking website visitor statistics. But, departments and entities using Google Analytics should abide by the procedures (PDF) outlined by the announcement of campus support of Google Analytics and other click-through agreements.
The standards described on this page may be used for vendor requirements. For example:
“Product must work with approximately 90% of our current usage.”