filter = function (v) {
                var parsed = parseFloat(v);
                return parsed >= from && parsed <= to;
            }
Return browsers market coverage.

@param {string[]} browsers Browsers names in Can I Use.
@param {string} [country="global"] Which country statistics should be used.

@return {number} Total market coverage for all selected browsers.

@example
browserslist.coverage(browserslist('> 1% in US'), 'US') //=> 83.1