ChartJS - Line Chart - Y axis scale problem ?

Line Chart - Y axis scale problem ?

HTML

<script src="http://www.chartjs.org/assets/Chart.js"></script>
<body>
  <h3>Working Chart</h3>
  <canvas id="pie-chart" height="450" width="600"></canvas>
</body>

CSS

canvas {
  background-color: #eee;
}

JavaScript

var data = [{
  value: 83,
  color: "#2DB45C",
  highlight: "#FF5A5E",
  labelFontSize: '16',
  label: "Masculino"
}, {
  value: 181,
  color: "#46BFBD",
  highlight: "#5AD3D1",
  label: "Feminino"
}];
var el = document.getElementById("pie-chart").getContext("2d");
var pie = new Chart(el).Pie(data, {
  tooltipTemplate: '<%= value + "%" %>'
});