{

  "title":{
    "text":"Test stacked bar charts",
    "style":"{font-size:16px;}"
  },

  "elements":[
    {
      "type":      "bar_stack",
      "colour":    "#FFB900",
      "text":      "Stack",
      "font-size": 10,
      "values" :   [
                    [{"val":5},{"val":5}],[{"val":2.5},{"val":5},{"val":2.5}],null,
                    [{"val":5},{"val":5},{"val":2},{"val":2},{"val":2,"colour":"#ff00ff"},{"val":2},{"val":2}]
                   ]
    },
    {
      "type":      "bar",
      "colour":    "#9933CC",
      "text":      "Bar",
      "font-size": 10,
      "values" :   [9,6,7,9]
    }
  ],

  "x_axis":{
    "max":4,
    "steps": 2,
    "labels":["January","February","March","April"]
  },

  "y_axis":{
    "max": 20
  }
}
