Google图表：在两轴堆叠的条形图中添加一条线

Question

我尝试过使用连击，或者只是添加了一个线系列，但是最终将这些条推到同一根轴上。我正在尝试获取下面的代码以在图像中添加一行。该代码仅用于使栏杆正常工作的上下文。

google.load('visualization', '1.1', {
    'packages': ['bar', 'corechart']
});
google.setOnLoadCallback(drawStuff);

function drawStuff() {
    var data = new google.visualization.DataTable();
    data.addColumn('string', 'Stuff');
    data.addColumn('number', 'Things');
    data.addColumn('number', 'Clutter');
    data.addColumn('number', 'Important');
    data.addColumn('number', 'Meh');
    data.addRows([
        ['2001', 321, 621, 816, 319],
        ['2002', 163, 231, 539, 594],
        ['2003', 125, 819, 123, 578],
        ['2004', 197, 536, 613, 298]
    ]);

    // Set chart options
    var options = {
        isStacked: true,
        series: {
            2: {
                targetAxisIndex: 1
            },
            3: {
                targetAxisIndex: 1
            },
        }
    };

    // Instantiate and draw our chart, passing in some options.
    var chart = new google.charts.Bar(document.getElementById('chart_div'));
    chart.draw(data, google.charts.Bar.convertOptions(options));
};