Cumulative value of each interval in a series (keen-dataviz.js)

Append a new series showing the cumulative value of an interval query

HTML

<script src="//d26b395fwzu5fz.cloudfront.net/keen-dataviz-1.1.3.js"></script>
<script src="//d26b395fwzu5fz.cloudfront.net/keen-analysis-1.2.2.js"></script>
<link rel="stylesheet" href="//d26b395fwzu5fz.cloudfront.net/keen-dataviz-1.1.3.css">
<div id="chart"></div>

JavaScript

var client = new Keen({
  projectId: "59c898d9c9e77c0001572499",
  readKey: "4497FE5F72EB84ADF7F071B637443B4D5CF65C7D568E79277B6374F1AC93CFFB2A984CA55FB4EC22531C956B69B8CF6AF628CD37C524CC14C7BC23471FCB813D020ADFE807C42A1A65C8CCBB10C809402254DAB5B3F0926CBA59FE01196E1801"
});
var chart = new Keen.Dataviz()
  .el('#chart')
  .type("bar")
  .height(500)
  .prepare();

// Use keen-analysis.js to run a query
// and pass the result into your chart:
client
  .query('count', {
    event_collection: 'sessions',
    timeframe: {
      start: "2018-07-02T00:00:00.000-00:00",
      end: "2018-08-01T00:00:00.000-00:00"
    },
    group_by: "meeting.name",
    order_by: [
    {
      property_name: 'result',
      direction:'DESC'
    }
    ],
    filters: [
    {
      property_name: 'session.original_url',
      operator: 'contains',
      property_value: '?utm_source=ONPEAK&utm_medium=AM'
    }
  ]
  })
  .then(function(res) {
    // Handle the result
    chart
      .data(res)
      .render();
  })
  .catch(function(err) {
    // Handle the error
    chart
      .message(err.message);
  });