riesSet = [];
    this.currentValueRange = 1;
    this.currentVisMinValue = 0;
    this.lastRenderTimeMillis = 0;
  }

  SmoothieChart.defaultChartOptions = {
    millisPerPixel: 20,
    enableDpiScaling: true,
    yMinFormatter: function(min, precision) {
      return parseFloat(min).toFixed(precision);
    },
    yMaxFormatter: function(max, precision) {
      return parseFloat(max).toFixed(precision);
    },
    maxValueScale: 1,
    minValueScale: 1,
    interpolation: 'bezier',
    scaleSmoothing: 0.12