const chart = Highcharts.chart('container', {
    chart: {
        type: 'line'
    },
    xAxis: {
        categories: [
            'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep',
            'Oct', 'Nov', 'Dec'
        ]
    },
    series: [{
        data: [29.9, 71.5, 106.4, 129.2, 144.0, 176.0, 135.6, 148.5, {
            y: 216.4,
            id: 'highest'
        }, 194.1, 95.6, 54.4]
    }]
});

document.getElementById('button').addEventListener('click', () => {
    const highest = chart.get('highest');
    if (highest) {
        highest.remove();
    }
});
