code: function (init) {
  		var series = this,
  			chart = series.chart,
  			clipRect = series.clipRect,
  			animation = series.options.animation;
  
  		if (animation && !isObject(animation)) {
  			animation = {};
  		}
  
  		if (init) { // initialize the animation
  			if (!clipRect.isAnimating) { // apply it only for one of the series
  				clipRect.attr('width', 0);
  				clipRect.isAnimating = true;
  			}
  
  		} else { // run the animation
  			clipRect.animate({
  				width: chart.plotSizeX
  			}, animation);
  
  			// delete this function to allow it only once
  			this.animate = null;
  		}
  	}
docs: Animate in the series