Preloading multiple mp3's using a looping array

I am preloading multiple mp3’s dynamically using a looping array and it is working very well. However, I would like to display the percetage of the last mp3 loaded by the array. Does anyone know how I would modify the code to do this:

 
 
var my_array:Array = new Array();
my_array[0] = "Audio/audio_1.mp3";
my_array[1] = "Audio/audio_2.mp3";
my_array[2] = "Audio/audio_3.mp3";
my_array[3] = "Audio/audio_4.mp3";
count = 0;
var k;
for (k in my_array) {
var my_audio:Sound = new Sound();
my_audio.loadSound(my_array[k], true);
my_audio.setVolume(0);
var my_interval2:Number;
my_interval2 = setInterval(checkAudioProgress, 100, my_audio);
function checkAudioProgress(the_audio:Sound):Void {
var AudioKBytes = Math.ceil(the_audio.getBytesTotal()/1024);
var AudioPct:Number = Math.round(the_audio.getBytesLoaded()/the_audio.getBytesTotal()*100);
AudioPctOutput = "Loading Audio: "+AudioPct+"%"+" of "+AudioKBytes+" k";
}
count++;
}
 

I’m working against a deadline so any extra help would be greatly appreciated.
Many Thanks.