I wanted to buy a CD of Avial and their Record Label website said this:

The market share of Firefox is at least 30%. This says it is 45%. However, let’s assume that it is only 20%. How the hell can any business choose to ignore 20%? Wow!
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This also says (w3schools).
These facts indicate that the browser figures above are not 100% realistic. Other web sites have statistics showing that Internet Explorer is used by at least 80% of the users.
Ok let's say IE is used by 80%, how can you ignore 20% of your user base?