[AS2] Add 1 to a variable outside a function from within

programming flash
1

I want to import a new image ever 5 seconds but how can I incriment the counter variable from within the function?

count=0;
function loadimage(count) {
	trace(count);
           count++;
	loadMovie("images/"+q+"/"+a+"/"+count+".jpg", mc_slideshow);
}

loadMovie("images/"+q+"/"+a+"/"+count+".jpg", mc_slideshow);

intervalID = setInterval(loadimage, 5000, count);

Thanks