Count up with xml value?

Hi Everybody,

I have a problem with xml, i’m getting a value from xml file, for example “1000”. Here is the code

var my_xml = new XML ();
my_xml.ignoreWhite = true;
my_xml.load ("data.xml");
my_xml.onLoad = function (success)
{
if (success)
show_txt.text = this.firstChild.childNodes[0];
}

How can i add +1 in every four seconds? i tried with this code but it doesnt work.

Example count up code

var curcount:Number = 1000000;
var maxcount:Number = 6000000000000;
var increment:Number = 1;

txt.autoSize = true;

var si:Number = setInterval(function ()
{
(curcount >= maxcount) ? clearInterval(si) : curcount += increment;
txt.text = String(curcount);
}, 1000);

Thanks