function drawChartTreatmentsPerYear() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['2020', 1],
    ['2019', 9],
    ['2010', 5],
    ['1993', 5],
    ['1959', 1],
    ['1949', 1],
    ['1912', 1],
    ['1877', 1],
    ['1875', 1],
    ['1859', 2],
    ['1857', 1],
    ['1856', 1],
    ['1849', 1],
    ['1822', 2]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Year (n=32)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerYear', 'pie', 14, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerYear'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerYear);