Bar and line chart combination in dimple

Bar and line chart combination using dimple.js library. Very simple and straightforward. Not much chart configuration options that why it's called a simple chart.

HTML

<script src="http://dimplejs.org/dist/dimple.v1.1.3.min.js"></script>
<div id="chartContainer">

JavaScript

var svg = dimple.newSvg("#chartContainer", 800, 400);

// Data hack required to get revenue and profit on the same axis, units are
// arbitrarily allocated to revenue but the values will be summed by date
var data = [{
    "Month": "01/2013",
    "Metric": "Revenue",
    "Revenue/Profit": 2000,
    "Units": 4
}, {
    "Month": "02/2013",
    "Metric": "Revenue",
    "Revenue/Profit": 3201,
    "Units": 3
}, {
    "Month": "03/2013",
    "Metric": "Revenue",
    "Revenue/Profit": 1940,
    "Units": 5
}, {
    "Month": "04/2013",
    "Metric": "Revenue",
    "Revenue/Profit": 2500,
    "Units": 1
}, {
    "Month": "05/2013",
    "Metric": "Revenue",
    "Revenue/Profit": 800,
    "Units": 4
}, {
    "Month": "01/2013",
    "Metric": "Profit",
    "Revenue/Profit": 2000,
    "Units": 0
}, {
    "Month": "02/2013",
    "Metric": "Profit",
    "Revenue/Profit": 2000,
    "Units": 0
}, {
    "Month": "03/2013",
    "Metric": "Profit",
    "Revenue/Profit": 14000,
    "Units": 0
}, {
    "Month": "04/2013",
    "Metric": "Profit",
    "Revenue/Profit": 3200,
    "Units": 0
}, {
    "Month": "05/2013",
    "Metric": "Profit",
    "Revenue/Profit": 1200,
    "Units": 0
}];

var chart = new dimple.chart(svg, data);
chart.setBounds(60, 20, 680, 330);

// Add your x axis - nothing unusual here
var x = chart.addCategoryAxis("x", "Month");
// First y axis is the combination axis for revenue and profit
var y1 = chart.addMeasureAxis("y", "Revenue/Profit");
// Second is the units only
var y2 = chart.addMeasureAxis("y", "Units");

// Plot the bars first - the order of series determines their dom position
// from back to front, this means bars are at the back.  It's important
// to note that the string here "Unit Sales" is NOT in the data.  Any string
// not in the data is just used to apply a label which can be used for colouring
// as it is here and will also appear in tool tips
var bars = chart.addSeries("Unit Sales", dimple.plot.bar, [x, y2]);
// Use a simple line by metric for...