function drawChartTreatmentsPerYear() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['1975', 2],
    ['1938', 3],
    ['1923', 10],
    ['1910', 2],
    ['1903', 2],
    ['1901', 2],
    ['1877', 2],
    ['1867', 4],
    ['1857', 3],
    ['1855', 2],
    ['1831', 26],
    ['1822', 2],
    ['1801', 3],
    ['1775', 10],
    ['1766', 2],
    ['Other (37)', 38]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Year (n=113)',
    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);