Syncing value axis across multiple chart instances

HTML

<script type="text/javascript" src="http://www.amcharts.com/lib/3/amcharts.js"></script>
<script type="text/javascript" src="http://www.amcharts.com/lib/3/serial.js"></script>
<script type="text/javascript" src="http://www.amcharts.com/lib/3/themes/none.js"></script>
<div id="chartdiv"></div>
<div id="chartdiv2"></div>

CSS

#chartdiv, #chartdiv2 {
	width		: 49%;
	height		: 500px;
	font-size	: 11px;
    float: left;
}

JavaScript

var chart1 = AmCharts.makeChart("chartdiv", {
    "type": "serial",
    "theme": "none",
    "autoMargins": false,
    "marginBottom": 70,
    "marginLeft": 50,
    "dataProvider": [{
        "country": "USA",
        "visits": 2025
    }, {
        "country": "China",
        "visits": 1882
    },{
        "country": "Germany",
        "visits": 1322
    },{
        "country": "France",
        "visits": 1114
    },{
        "country": "Spain",
        "visits": 711
    },{
        "country": "Russia",
        "visits": 580
    }, {
        "country": "Canada",
        "visits": 441
    }],
    "valueAxes": [{
        "gridColor":"#FFFFFF",
		"gridAlpha": 0.2,
		"dashLength": 0
    }],
    "gridAboveGraphs": true,
    "startDuration": 1,
    "graphs": [{
        "balloonText": "[[category]]: <b>[[value]]</b>",
        "fillAlphas": 0.8,
        "lineAlpha": 0.2,
        "type": "column",
        "valueField": "visits"		
    }],
    "chartCursor": {
        "categoryBalloonEnabled": false,
        "cursorAlpha": 0,
        "zoomable": false
    },
    "categoryField": "country",
    "categoryAxis": {
        "gridPosition": "start",
        "gridAlpha": 0,
        "labelRotation": 45
    },
	"exportConfig":{
	  "menuTop": 0,
	  "menuItems": [{
      "icon": '/lib/3/images/export.png',
      "format": 'png'	  
      }]  
	}
});

// we will need to wait for the first chart to initialize so we know its minimum and maximum values which we can use for the second chart
chart1.addListener('init', function () {
    var chart2 = AmCharts.makeChart("chartdiv2", {
        "type": "serial",
        "theme": "none",
        "autoMargins": false,
        "marginBottom": 70,
        "marginLeft": 50,
        "dataProvider": [{
            "country": "UK",
            "visits": 1122
        }, {
            "country": "India",
            "visits": 984
        }, {
            "country": "Netherlands",
            "visits": 665
        }, {
            "country": "South Korea",
...