function drawChartTreatmentsPerYear() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['2020', 18],
    ['2019', 34],
    ['2017', 147],
    ['2016', 21],
    ['2014', 28],
    ['2012', 32],
    ['2011', 52],
    ['2010', 38],
    ['2009', 64],
    ['2008', 68],
    ['2007', 49],
    ['2006', 17],
    ['2005', 35],
    ['2004', 20],
    ['1998', 16],
    ['Other (16)', 75]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Year (n=714)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerYear', 'pie', 16, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerYear'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerYear);