Syncing Tooltip across Multiple JavaScript Charts & Graphs

window.onload = function () {
  var charts = [];
  var axisX = {
    labelFormatter: function(){ return "";},
    tickLength: 0,
    lineThickness: 0
  }, 
  axisY = {
    labelFormatter: function(){ return "";},
    tickLength: 0,
    gridThickness: 0,
  };
  
  var newUserOptions = {
    animationEnabled: true,
    theme: "light2",
    title:{
      text: "New Users",
      fontSize: 18,
      verticalAlign: "bottom"
    },
    axisX: axisX,
    axisY: axisY,
    data: [{
      type: "splineArea", //change type to bar, line, area, pie, etc
      markerSize: 0,
      dataPoints: [
        { x: new Date(2018, 00, 01), y: 74553 },
        { x: new Date(2018, 01, 01), y: 75374 },
        { x: new Date(2018, 02, 01), y: 76065 },
        { x: new Date(2018, 03, 01), y: 76521 },
        { x: new Date(2018, 04, 01), y: 76695 },
        { x: new Date(2018, 05, 01), y: 76381 },
        { x: new Date(2018, 06, 01), y: 76693 },
        { x: new Date(2018, 07, 01), y: 75624 },
        { x: new Date(2018, 08, 01), y: 76367 },
        { x: new Date(2018, 09, 01), y: 75426 },
        { x: new Date(2018, 10, 01), y: 76024 },
        { x: new Date(2018, 11, 01), y: 75960 }
      ]
    }]
  }
  var bounceRateOptions = {
    animationEnabled: true,
    theme: "light2",
    title:{
      text: "Bounce Rate",
      fontSize: 18,
      verticalAlign: "bottom"
    },
    axisX: axisX,
    axisY: axisY,
    data: [{
      type: "splineArea", //change type to bar, line, area, pie, etc
      markerSize: 0,
      yValueFormatString: "#.##%",
      dataPoints: [
        { x: new Date(2018, 00, 01), y: 0.4731 },
        { x: new Date(2018, 01, 01), y: 0.4743 },
        { x: new Date(2018, 02, 01), y: 0.4760 },
        { x: new Date(2018, 03, 01), y: 0.4751 },
        { x: new Date(2018, 04, 01), y: 0.4757 },
        { x: new Date(2018, 05, 01), y: 0.4761 },
        { x: new Date(2018, 06, 01), y: 0.4768 },
        { x: new Date(2018, 07, 01), y: 0.4771 },
        { x: new Date(2018, 08, 01), y: 0.4773 },
        { x: new Date(2018, 09, 01), y: 0.4764 },
        { x: new Date(2018, 10, 01), y: 0.4757 },
        { x: new Date(2018, 11, 01), y: 0.4751 }
      ]
    }]
  }
  
  var pageViewsOptions = {
    animationEnabled: true,
    theme: "light2",
    title:{
      text: "Page Views",
      fontSize: 18,
      verticalAlign: "bottom"
    },
    axisX: axisX,
    axisY: axisY,
    data: [{
      type: "splineArea", //change type to bar, line, area, pie, etc
      markerSize: 0,
      dataPoints: [
        { x: new Date(2018, 00, 01), y: 897533 },
        { x: new Date(2018, 01, 01), y: 898699 },
        { x: new Date(2018, 02, 01), y: 900047 },
        { x: new Date(2018, 03, 01), y: 900348 },
        { x: new Date(2018, 04, 01), y: 900678 },
        { x: new Date(2018, 05, 01), y: 900407 },
        { x: new Date(2018, 06, 01), y: 900946 },
        { x: new Date(2018, 07, 01), y: 901937 },
        { x: new Date(2018, 08, 01), y: 902117 },
        { x: new Date(2018, 09, 01), y: 901936 },
        { x: new Date(2018, 10, 01), y: 903288 },
        { x: new Date(2018, 11, 01), y: 903107 }
      ]
    }]
  }

  var visitorsOptions = {
    animationEnabled: true,
    theme: "light2", // "light1", "light2", "dark1", "dark2"
    title:{
      text: "Total Website Visitors"
    },
    axisY: {
      labelFormatter: addSymbols
    },
    data: [{
      type: "column", //change type to bar, line, area, pie, etc
      color: "#6D78AD",
      dataPoints: [
        { x: new Date(2018, 00, 01), y: 130796 },
        { x: new Date(2018, 01, 01), y: 131774 },
        { x: new Date(2018, 02, 01), y: 132750 },
        { x: new Date(2018, 03, 01), y: 132850 },
        { x: new Date(2018, 04, 01), y: 133384 },
        { x: new Date(2018, 05, 01), y: 132607 },
        { x: new Date(2018, 06, 01), y: 132687 },
        { x: new Date(2018, 07, 01), y: 132443 },
        { x: new Date(2018, 08, 01), y: 133044 },
        { x: new Date(2018, 09, 01), y: 132095 },
        { x: new Date(2018, 10, 01), y: 132446 },
        { x: new Date(2018, 11, 01), y: 131648 }
      ]
    }]
  };

  charts.push(new CanvasJS.Chart("chartContainer1", visitorsOptions));
  charts.push(new CanvasJS.Chart("chartContainer2", newUserOptions));
  charts.push(new CanvasJS.Chart("chartContainer3", pageViewsOptions));
  charts.push(new CanvasJS.Chart("chartContainer4", bounceRateOptions));
  syncTooltip(charts);
  
  for( var i = 0; i < charts.length; i++){
    charts[i].render();
  }

  function syncTooltip(charts) {
    
    if(!this.onToolTipUpdated){
      this.onToolTipUpdated = function(e) {
        for (var j = 0; j < charts.length; j++) {
          if (charts[j] != e.chart)
            charts[j].toolTip.showAtX(e.entries[0].xValue);
        }
      }
    }

    if(!this.onToolTipHidden){
      this.onToolTipHidden = function(e) {
        for( var j = 0; j < charts.length; j++){
          if(charts[j] != e.chart)
            charts[j].toolTip.hide();
        }
      }
    }
    
    for(var i = 0; i < charts.length; i++) { 
        if(!charts[i].options.toolTip)
          charts[i].options.toolTip = {};

        charts[i].options.toolTip.updated = this.onToolTipUpdated;
        charts[i].options.toolTip.hidden = this.onToolTipHidden;
    }  
  }

  function addSymbols(e){
      var suffixes = ["", "K", "M", "B"];

      var order = Math.max(Math.floor(Math.log(Math.abs(e.value)) / Math.log(1000)), 0);
      if(order > suffixes.length - 1)
          order = suffixes.length - 1;

      var suffix = suffixes[order];
      return CanvasJS.formatNumber(e.value / Math.pow(1000, order)) + suffix;
  }
}