ndomData() {

      if (data.length > 0) {
        data = data.slice(1)
      }

      // Do a random walk
      while (data.length < totalPoints) {

        var prev = data.length > 0 ? data[data.length - 1] : 50,
            y    = prev + Math.random() * 10 - 5

        if (y < 0) {
          y = 0
        } else if (y > 100) {
          y = 100
        }

        data.push(y)
      }

      // Zip the generated y values with the x values
      var res = []
      for (var i = 0; i < data.length; ++i) {
  