# Chart.js - StackedArea Chart

### Introduction

A stacked area chart is a line chart extension that is optimized for stacked data.

<div class=“canvas-holder”> <canvas width=“250” height=“125”></canvas> </div>

### Example usage

    var myStackedAreaChart = new Chart(ctx).StackedArea(data, options);

### Data structure

    var data = {
        labels: ["January", "February", "March", "April", "May", "June", "July"],
        datasets: [
            {
                label: "My First dataset",
                fillColor: "rgba(220,220,220,0.5)",
                strokeColor: "rgba(220,220,220,0.8)",
                highlightFill: "rgba(220,220,220,0.75)",
                highlightStroke: "rgba(220,220,220,1)",
                data: [65, 59, 80, 81, 56, 55, 40]
            },
            {
                label: "My Second dataset",
                fillColor: "rgba(151,187,205,0.5)",
                strokeColor: "rgba(151,187,205,0.8)",
                highlightFill: "rgba(151,187,205,0.75)",
                highlightStroke: "rgba(151,187,205,1)",
                data: [28, 48, 40, 19, 86, 27, 90]
            }
        ]
    };

### Chart Options

These are the customisation options specific to StackedArea charts. These options are merged with the global chart configuration options, and form the options of the standard line chart.

    {
        //Boolean - Whether points should be rendered on a percentage base
        relativePoints : false,
    }

You can override these for your `Chart` instance by passing a second argument into the `StackedArea` method as an object with the keys you want to override.

For example, we could have a stacked point chart without a stroke on each point by doing the following:

    new Chart(ctx).StackedArea(data, {
        relativePoints: true
    });
    // This will create a chart with all of the default options, merged from the global config,
    //  and the StackedArea chart defaults but this particular instance will have `relativePoints` set to true.