Highcharts Demo - Area with missing points

$(function () {
        $('#container').highcharts({
            chart: {
                type: 'area',
                spacingBottom: 30
            },
            title: {
                text: 'Fruit consumption *'
            },
            subtitle: {
                text: '* Jane\'s banana consumption is unknown',
                floating: true,
                align: 'right',
                verticalAlign: 'bottom',
                y: 15
            },
            legend: {
                layout: 'vertical',
                align: 'left',
                verticalAlign: 'top',
                x: 150,
                y: 100,
                floating: true,
                borderWidth: 1,
                backgroundColor: '#FFFFFF'
            },
            xAxis: {
                categories: ['Apples', 'Pears', 'Oranges', 'Bananas', 'Grapes', 'Plums', 'Strawberries', 'Raspberries']
            },
            yAxis: {
                title: {
                    text: 'Y-Axis'
                },
                labels: {
                    formatter: function() {
                        return this.value;
                    }
                }
            },
            tooltip: {
                formatter: function() {
                    return '<b>'+ this.series.name +'</b><br/>'+
                    this.x +': '+ this.y;
                }
            },
            plotOptions: {
                area: {
                    fillOpacity: 0.5
                }
            },
            credits: {
                enabled: false
            },
            series: [{
                name: 'John',
                data: [0, 1, 4, 4, 5, 2, 3, 7]
            }, {
                name: 'Jane',
                data: [1, 0, 3, null, 3, 1, 2, 1]
            }]
        });
    });
    

/**
 * Grid theme for Highcharts JS
 * @author Torstein Hønsi
 */

Highcharts.theme = {
   colors: ['#058DC7', '#50B432', '#ED561B', '#DDDF00', '#24CBE5', '#64E572', '#FF9655', '#FFF263', '#6AF9C4'],
   chart: {
      backgroundColor: {
         linearGradient: { x1: 0, y1: 0, x2: 1, y2: 1 },
         stops: [
            [0, 'rgb(255, 255, 255)'],
            [1, 'rgb(240, 240, 255)']
         ]
      },
      borderWidth: 2,
      plotBackgroundColor: 'rgba(255, 255, 255, .9)',
      plotShadow: true,
      plotBorderWidth: 1
   },
   title: {
      style: {
         color: '#000',
         font: 'bold 16px "Trebuchet MS", Verdana, sans-serif'
      }
   },
   subtitle: {
      style: {
         color: '#666666',
         font: 'bold 12px "Trebuchet MS", Verdana, sans-serif'
      }
   },
   xAxis: {
      gridLineWidth: 1,
      lineColor: '#000',
      tickColor: '#000',
      labels: {
         style: {
            color: '#000',
            font: '11px Trebuchet MS, Verdana, sans-serif'
         }
      },
      title: {
         style: {
            color: '#333',
            fontWeight: 'bold',
            fontSize: '12px',
            fontFamily: 'Trebuchet MS, Verdana, sans-serif'

         }
      }
   },
   yAxis: {
      minorTickInterval: 'auto',
      lineColor: '#000',
      lineWidth: 1,
      tickWidth: 1,
      tickColor: '#000',
      labels: {
         style: {
            color: '#000',
            font: '11px Trebuchet MS, Verdana, sans-serif'
         }
      },
      title: {
         style: {
            color: '#333',
            fontWeight: 'bold',
            fontSize: '12px',
            fontFamily: 'Trebuchet MS, Verdana, sans-serif'
         }
      }
   },
   legend: {
      itemStyle: {
         font: '9pt Trebuchet MS, Verdana, sans-serif',
         color: 'black'

      },
      itemHoverStyle: {
         color: '#039'
      },
      itemHiddenStyle: {
         color: 'gray'
      }
   },
   labels: {
      style: {
         color: '#99b'
      }
   },

   navigation: {
      buttonOptions: {
         theme: {
            stroke: '#CCCCCC'
         }
      }
   }
};

// Apply the theme
var highchartsOptions = Highcharts.setOptions(Highcharts.theme);