function drawChartTreatmentsPerYear() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['2023', 13],
    ['2022', 15],
    ['2021', 7],
    ['2020', 6],
    ['2018', 17],
    ['2015', 296],
    ['2014', 9],
    ['2012', 4],
    ['2011', 11],
    ['2007', 14],
    ['1981', 39],
    ['1976', 11],
    ['1975', 8],
    ['1973', 9],
    ['1972', 6],
    ['Other (8)', 11]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Year (n=476)',
    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);