Multidimensional Drilldown with back button

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>
<div id="chartdiv"></div>

CSS

#chartdiv {
	width	: 100%;
	height	: 500px;
    font-size: 11px;
}

JavaScript

var chart;
var chartTitle       = "Base";
var chartDataIndexes = [];
var chartData        = [{
    "date": "2009-01-01",
    "value": 3,
    "fromValue": 2,
    "toValue": 5
},{
    "date": "2009-02-01",
    "value": 5,
    "fromValue": 4,
    "toValue": 6
}, {
    "date": "2009-03-01",
    "value": 15,
    "fromValue": 12,
    "toValue": 18,
    //"bullet": "round",
    "subSetTitle": "Second level",
    "subSet" : [{
        "date": "2009-03-01",
        "value": 3,
        "fromValue": 2,
        "toValue": 5
    },{
        "date": "2009-03-02",
        "value": 3,
        "fromValue": 2,
        "toValue": 5
    },{
        "date": "2009-03-03",
        "value": 3,
        "fromValue": 2,
        "toValue": 5
    },{
        "date": "2009-03-04",
        "value": 3,
        "fromValue": 2,
        "toValue": 5,
        "bullet": "round",
        "subSetTitle": "Third level",
        "subSet": [{
            "date": "2009-03-04 01:00",
            "value": 3,
            "fromValue": 2,
            "toValue": 5
        },{
            "date": "2009-03-04 02:00",
            "value": 4,
            "fromValue": 3,
            "toValue": 6
        },{
            "date": "2009-03-04 03:00",
            "value": 5,
            "fromValue": 4,
            "toValue": 6,
            "bullet": "round",
            "subSetTitle": "Fourth level",
            "subSet": [{
                "date": "2009-03-04 03:10",
                "value": 3,
                "fromValue": 2,
                "toValue": 5
            },{
                "date": "2009-03-04 03:20",
                "value": 2,
                "fromValue": 1,
                "toValue": 3
            },{
                "date": "2009-03-04 03:30",
                "value": 3,
                "fromValue": 2,
                "toValue": 5
            },{
                "date": "2009-03-04 03:40",
                "value": 4,
                "fromValue": 3,
                "toValue": 5
            },{
            ...