googlecharts calendar customized tutorial

Code

<html>
<head>
<title>Google Charts tutorial Tutorial</title>
   <script type="text/javascript" src="https://www.gstatic.com/charts/loader.js"></script>
   <script type="text/javascript">
     google.charts.load('current', {packages: ['corechart','calendar']});     
   </script>
</head>
<body>
<div id="container" style="width: 550px; height: 400px; margin: 0 auto"></div>
<script language="JavaScript">
function drawChart() {
   // Define the chart to be drawn.
   var data = new google.visualization.DataTable();
     data.addColumn({ type: 'date', id: 'Date' });
       data.addColumn({ type: 'number', id: 'Students' });
       data.addRows([
          [ new Date(2012, 3, 13), 50 ],
          [ new Date(2012, 3, 14), 50 ],
          [ new Date(2012, 3, 15), 49 ],
          [ new Date(2012, 3, 16), 48 ],
          [ new Date(2012, 3, 17), 50 ],   
          [ new Date(2012, 4, 1), 50 ],
          [ new Date(2012, 4, 2), 50 ],
          [ new Date(2012, 4, 3), 49 ],
          [ new Date(2012, 4, 4), 48 ],
          [ new Date(2012, 4, 5), 50 ],  
          [ new Date(2012, 5, 4), 40 ],
          [ new Date(2012, 5, 5), 50 ],
          [ new Date(2012, 5, 10), 48 ],
          [ new Date(2012, 5, 11), 50 ],
          [ new Date(2012, 5, 12), 42 ],
          [ new Date(2012, 5, 20), 45 ],
          [ new Date(2012, 5, 21), 46 ],
          [ new Date(2012, 5, 29), 45 ],
		  [ new Date(2013, 3, 13), 40 ],
          [ new Date(2013, 3, 14), 40 ],
          [ new Date(2013, 3, 15), 39 ],
          [ new Date(2013, 3, 16), 38 ],
          [ new Date(2013, 3, 17), 40 ],   
          [ new Date(2013, 4, 1), 40 ],
          [ new Date(2013, 4, 2), 40 ],
          [ new Date(2013, 4, 3), 49 ],
          [ new Date(2013, 4, 4), 48 ],
          [ new Date(2013, 4, 5), 40 ],
          [ new Date(2013, 5, 4), 40 ],
          [ new Date(2013, 5, 5), 50 ],
          [ new Date(2013, 5, 12), 48 ],
          [ new Date(2013, 5, 13), 40 ],
          [ new Date(2013, 5, 19), 32 ],
          [ new Date(2013, 5, 23), 45 ],
          [ new Date(2013, 5, 24), 36 ],
          [ new Date(2013, 5, 30), 45 ]
        ]);

// Set chart options
   var options = {'title':'Attendence',
      'width':550,
      'height':400,
      calendar: {
         yearLabel: {
           fontName: 'Times-Roman',
           fontSize: 32,
           color: '#1A8763',
           bold: true,
           italic: true
         },
         monthOutlineColor: {
            stroke: '#981b48',
            strokeOpacity: 0.8,
            strokeWidth: 2
         },
         unusedMonthOutlineColor: {
           stroke: '#bc5679',
           strokeOpacity: 0.8,
           strokeWidth: 1
         }		 
      }
   };

// Instantiate and draw the chart.
   var chart = new google.visualization.Calendar(document.getElementById('container'));
   chart.draw(data, options);
}
google.charts.setOnLoadCallback(drawChart);
</script>
</body>
</html>

Result