var chart = new PieChart(element, data, {
  pie : {
    chart : {
      type : 'doughnut',
      width : 50,
    },
    color : ['#CDDC39', '#4CAF50', '#009688', '#00BCD4', '#2196F3', '#3F51B5', '#673AB7'],
    radius : 250,
    cornerRadius : 3,
    padding : 1,
    curve :360,
    startAngle : 0
  },
  margin: {
    left: 0,
    right: 0,
    top: 0,
    bottom: 0
  },
  transition: {
    animate: true,
    duration : 2000
  },
  tooltip: {
    show : true,
    listener : 'click touchstart',
    class : 'custom-tooltip',
    formatter : function() {
      return this.yValue + ' units 
in ' + this.xValue;
    },
  },
  legend : {
    show : true,
    position : 'center',
  }
});