function drawChartTreatmentsPerYear() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['2018', 21],
    ['2017', 9],
    ['2016', 24],
    ['2012', 18],
    ['2008', 27],
    ['2006', 31],
    ['2003', 10],
    ['2001', 15],
    ['1900', 23],
    ['1898', 10],
    ['1889', 8],
    ['1886', 33],
    ['1885', 12],
    ['1859', 14],
    ['1819', 26],
    ['Other (63)', 173]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Year (n=454)',
    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);