Google Charts 100% Stacked Stepped Chart

Google Charts 100% Stacked Stepped Chart

<html>
   <head>
      <title>Google Charts Tutorial</title>
      <script type = "text/javascript" src = "https://www.gstatic.com/charts/loader.js">
      </script>
      <script type = "text/javascript" src = "https://www.google.com/jsapi">
      </script>
      <script type = "text/javascript">
         google.charts.load('current', {packages: ['corechart']});     
      </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 = google.visualization.arrayToDataTable([
               ['Director (Year)',  'Rotten Tomatoes', 'IMDB'],
               ['Alfred Hitchcock (1935)', 8.4,         7.9],
               ['Ralph Thomas (1959)',     6.9,         6.5],
               ['Don Sharp (1978)',        6.5,         6.4],
               ['James Hawes (2008)',      4.4,         6.2]
            ]);

            var options = {
               title: 'The decline of \'The 39 Steps\'',
               vAxis: {title: 'Accumulated Rating'},
               isStacked: 'percent'      
            };

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