function drawChartTreatmentsPerYear() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['2021', 2],
    ['1988', 1],
    ['1941', 1],
    ['1924', 1],
    ['1922', 2],
    ['1911', 2],
    ['1907', 2],
    ['1906', 2],
    ['1891', 1],
    ['1879', 1],
    ['1878', 2],
    ['1877', 1],
    ['1875', 3],
    ['1859', 1],
    ['1829', 2],
    ['Other (7)', 7]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Year (n=31)',
    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);