var data = google.visualization.arrayToDataTable([
      ['Year', 'Sales', 'Expenses'],
      ['2004',  1000,      400],
      ['2005',  1170,      460],
      ['2006',  660,       1120],
      ['2007',  1030,      540]
    ]);

var data = new google.visualization.DataTable();
data.addColumn('string', 'Year');
data.addColumn('number', 'Sales');
data.addColumn('number', 'Expenses');
data.addRows([  ['2004', 1000 , 400], ['2005', 1170, 460], ['2006', 660, 1120], ['2007',1030,540]
  ]);

['Year', 'Sales', 'Expenses' , 'Other'],
['2004',  1000,      400     ,  232   ],
['2005',  1170,      460    ,  421   ],
['2006',  660,       1120    ,  4324  ],
['2007',  1030,      540     ,  4234  ],
['2008',  1530,      50     ,    234  ],

// function to update the chart with new data.
      function updateChart() {

          dataTable = new google.visualization.DataTable();

          var newData = [['Year', 'Sales', 'Expenses' , 'Other'],
            ['2004',  1000,      400     ,  232   ],
            ['2005',  1170,      460    ,  421   ],
            ['2006',  660,       1120    ,  4324  ],
            ['2007',  1030,      540     ,  4234  ],
            ['2008',  1530,      50     ,    234  ]];

          // determine the number of rows and columns.
          var numRows = newData.length;
          var numCols = newData[0].length;

          // in this case the first column is of type 'string'.
          dataTable.addColumn('string', newData[0][0]);

          // all other columns are of type 'number'.
          for (var i = 1; i < numCols; i++)
            dataTable.addColumn('number', newData[0][i]);

          // now add the rows.
          for (var i = 1; i < numRows; i++)
            dataTable.addRow(newData[i]);

          // redraw the chart.
          chart.draw(dataTable, options);

      }