abled: false }
    },
    area: {
      stacking: 'normal'
    }
  },
  xAxis: {
    type: 'datetime',
    ordinal: false,
    maxZoom: 10000 // three days
  },
  yAxis:[
    {
      min: 0,
      title: { text: 'Number of responses' },
      opposite: false,
      reversedStacks: false
    }, {
      min: 0,
      title: {
        text: 'Active Users',
        style: { color: '#FFA900' }
      },
      opposite: true
    }
  ],
  series: [
    {
color: '#5E7BE2',
name: 'All',
data: responses[0],
tooltip: {