How to add target line in google column chart?

Question

How to add the target line in google column chart like this.

Answer 1

You can use a Stepped Area series to achieve this. It's a little awkward but works well.

var data = google.visualization.arrayToDataTable([
    ['Month', 'Bolivia', 'Ecuador', 'Madagascar', 'Papua New Guinea', 'Rwanda', ''],
    ['2004/05',  165,      938,         522,             998,           450,      250],
    ['2005/06',  135,      1120,        599,             1268,          288,      250],
    ['2006/07',  157,      1167,        587,             807,           397,      250],
    ['2007/08',  139,      1110,        615,             968,           215,      250],
    ['2008/09',  136,      691,         629,             1026,          366,      250]
]);

var options = {
    seriesType: "line",
    series: {5: {
      type: "steppedArea", 
      color: '#FF0000', 
      visibleInLegend: false, 
      areaOpacity: 0}
    }
};

var chart = new google.visualization.LineChart(document.getElementById('chart_div'));    
chart.draw(data, options);

Example

Stepped Area Google Chart Example