function drawChartTreatmentsPerYear() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['2020', 9],
    ['2019', 6],
    ['2016', 5],
    ['2014', 4],
    ['2006', 6],
    ['1952', 4],
    ['1900', 2],
    ['1895', 3],
    ['1884', 22],
    ['1871', 14],
    ['1869', 15],
    ['1868', 8],
    ['1867', 147],
    ['1840', 9],
    ['1838', 7],
    ['Other (9)', 13]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Year (n=274)',
    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);