text: CanvasCharts.prototype.drawVBars = function(data, stepValue){
      //start a little away from the y-axis
      var x = this.startX + 10;
      //create the gradient for the line
      this.createGradient();
      //number of data points we need to plot
      var length = data.length;
      for(var i = 0 ; i < length ; i += 1){
          //draw line from the current data point to the next one
          this.drawLine(x, (this.containerHeight - 45), x, (this.containerHeight - data[i]), {"lineWidth": this.barHeight, "strokeStyle": this.barGradient});
          x += stepValue;
      }
  };
  