How to set an fillArea offset in HighCharts

Question

I try to set an reference value for a area-plot in higcharts. this should be similar to this example but with 100 as baseline. Because its hard to describe i attach a picture. I'm really lost on this topic, thanks for any help/hint in advance.

Answer 1

threshold was what im looking for. add it to the series, see jsfiddle

series: [{
    name: 'John',
    data: [105, 103, 104, 107, 102],
    threshold : 100
} ....

Answer 2

I don't think you can set the baseline to actually be anything other than 0, but what you can do is modify the axis such that it displays the actual value we're graphing offset by 100. Then for your data, you can offset it by the same amount in the opposite direction.

yAxis: {           
    labels: {
         formatter: function () {
             return [this.value + 100];
         }
    }
},
series: [{
        name: 'John',
        data: [105, 103, 104, 107, 102].offset(-100)
    }, {
        name: 'Jane',
        data: [102, 98, 97, 102, 101].offset(-100)
    }, {
        name: 'Joe',
        data: [103, 104, 104, 98, 105].offset(-100)
    }
]

Where

Array.prototype.offset = function (ofs) {
    var a = [];
    this.forEach(function (d) {
        a.push(d + ofs);
    });
    return a;
};

Doing that I created the graph you were hoping for:

JSFiddle