自定义标签求占比 https://help.fanruan.com/finereport/doc-view-4370.html
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function() {var points = this.series.points; //获取当前系列所有的数据点var total = 0;for (var i = 0, len = points.length; i < len; i++) {total += points[i].value; //求分类下的系列和}return this.value+" "+FR.contentFormat(this.value/total, '#0%'); //求占比}