title: Highcharts show max., min., and average for each serie in legend
body: <p>I'm having some charts where it would be nice to show <strong>minimum</strong>, <strong>maximum</strong> and <strong>average</strong> values for each serie separately. In the legend is not a "must", but it would be very nice. Another solution might be to show the min, max and actual value right in the chart (at the point), that would also be a very nice solution. Number of series varies from 1-4 at the moment, in different charts.</p>
  
  <p>Actual value (or the latest value actually) is already in the legend.</p>
  
  <p><em>In addition I want these values to be updated "at all times", both at first load and when changing zoom. When changing zoom it should be based on the selection, so when selecting "1 m" it must show the values for the last month and so on.</em></p>
  
  <p><a href="http://jsfiddle.net/dg4wpg0t/1/" rel="nofollow noreferrer">http://jsfiddle.net/dg4wpg0t/1/</a></p>
  
  <p>Any help is appreciated :)</p>
  
  <p>One example of final result (red text):
  <a href="https://i.stack.imgur.com/AAdLU.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/AAdLU.png" alt="Final result"></a></p>
  
  <pre><code>Highcharts.stockChart('container', {
  
  chart: {
      zoomType: 'x'
  },
  
  legend: {
      enabled: true,
      labelFormatter: function() {
          var lastVal = this.yData[this.yData.length - 1];
          return this.name + '&lt;br&gt;' + 'Now: ' + lastVal + ' °C';
          }
  },
  
    series: [{
      name: 'Outside',
      data: [
          [Date.UTC(2016, 01, 01), 0.2],
          [Date.UTC(2016, 01, 06), -1.4],
          [Date.UTC(2016, 01, 11), -2.6],
          [Date.UTC(2016, 01, 16), 11.1],
          [Date.UTC(2016, 01, 21), -11.1],
          [Date.UTC(2016, 01, 26), 3.7],
          [Date.UTC(2016, 02, 01), 4.9],
          [Date.UTC(2016, 02, 06), 8.2],
          [Date.UTC(2016, 02, 11), 0.2],
          [Date.UTC(2016, 02, 16), -1.4],
          [Date.UTC(2016, 02, 21), -2.6],
          [Date.UTC(2016, 02, 26), -5.1],
          [Date.UTC(2016, 03, 01), -8.3],
          [Date.UTC(2016, 03, 06), 3.7],
          [Date.UTC(2016, 03, 11), 4.9],
          [Date.UTC(2016, 03, 16), 5.2],
          [Date.UTC(2016, 03, 21), 0.2],
          [Date.UTC(2016, 03, 26), -1.4],
          [Date.UTC(2016, 04, 01), -2.6],
          [Date.UTC(2016, 04, 06), -5.1],
          [Date.UTC(2016, 04, 11), -8.3],
          [Date.UTC(2016, 04, 16), 11.2],
          [Date.UTC(2016, 04, 21), -11.2],
          [Date.UTC(2016, 04, 26), 5.2]
          ]
      }, {
      name: 'Inside',
      data: [
          [Date.UTC(2016, 01, 01), 17.8],
          [Date.UTC(2016, 01, 06), 27.1],
          [Date.UTC(2016, 01, 11), 17.1],
          [Date.UTC(2016, 01, 16), 21.7],
          [Date.UTC(2016, 01, 21), 25.3],
          [Date.UTC(2016, 01, 26), 24.3],
          [Date.UTC(2016, 02, 01), 22.3],
          [Date.UTC(2016, 02, 06), 24.1],
          [Date.UTC(2016, 02, 11), 19.8],
          [Date.UTC(2016, 02, 16), 20.2],
          [Date.UTC(2016, 02, 21), 26.5],
          [Date.UTC(2016, 02, 26), 21.7],
          [Date.UTC(2016, 03, 01), 25.3],
          [Date.UTC(2016, 03, 06), 24.3],
          [Date.UTC(2016, 03, 11), 22.3],
          [Date.UTC(2016, 03, 16), 24.1],
          [Date.UTC(2016, 03, 21), 19.8],
          [Date.UTC(2016, 03, 26), 20.2],
          [Date.UTC(2016, 04, 01), 24.5],
          [Date.UTC(2016, 04, 06), 21.7],
          [Date.UTC(2016, 04, 11), 27.2],
          [Date.UTC(2016, 04, 16), 17.2],
          [Date.UTC(2016, 04, 21), 22.3],
          [Date.UTC(2016, 04, 26), 24.1]
          ]
      }]
  
  });
  </code></pre>