Duplicate movie clip

I am writing a function that is duplicating a movie clip and put it on the stage.
My problem is that when I test my function the duplicate movies are put in the left corner of the stage at (0,0), and I what the to be on the center of the stage.
Here is my function:

function createBord() {
for(count = 0; count < 12; count++) {
_root.attachMovie(“border_mc”, “border_mc”, _root.getNextHighestDepth());
_root.border_mc.duplicateMovieClip(“bord”+count, _root.getNextHighestDepth());
eval(“bord”+count)._x = (count%4)*180;
eval(“bord”+count)._y = Math.floor(count/4)*180;
}
}

Thank you.