FlotChart绘制不同系列调用ajax

I am trying unsuccessfully to plot a graph with many series with flot chart (http://www.flotcharts.org/)

I call ajax and plot graph with:

$.ajax({ 
    type: 'POST', 
        url: 'include/ajax/Charts.php', 
        data: { var1: foo[8],
                var2: foo[6]  }, 
        dataType: 'json',
        success: function (data) { 
            $.plot("#Grafico", data, options);
        }
});

the result from Chart.php is:

{ "A1":{"label": "RECORD (A1) "
        "data": [[1999, 3.0], [2000, 3.9], [2001, 2.0], [2002, 1.2], [2003, 1.3], [2004, 2.5], [2005, 2.0], [2006, 3.1], [2007, 2.9], [2008, 0.9]]
       },
  "A2":{"label": "RECORD (A2) ",
        "data": [[1999, 5.0], [2000, 8.9], [2001, 2.0], [2002, 1.2], [2003, 1.3], [2004, 2.5], [2005, 2.0], [2006, 3.1], [2007, 2.9], [2008, 0.9]]
       } 
}

where A1 and A2 are the series.

thanks in advance for your help.

I found....

Json response change "A1" and "A2" to numbers "0", "1" ecc.

I count how many object in json:

var nn = Object.keys(serie).length;

declare my result:

var res = [];

and fill the result:

for (var i = 0; i < nn; i++){
    res.push(serie[i]);
}

and at the end plot the graph:

$.plot("#Grafico", res, options);

I did not understand how "push" works but now all series are plotted.