Score counter in AS3

Hi everyone,

The game I’m making is a shooter: alienships fly across the screen and when I click them, they die.

I want to have a dynamic text that keeps score of the number of ships I kill, but I’m not managing to do it.

I have a “Main class” and an “Alienship class” in my game. This code is in the “Alienship class”:

    function Alienship():void
    {
        addEventListener(MouseEvent.CLICK,whenclick);
    }

    private function whenclick(e:MouseEvent)
    {
        trace("You're dead

");
parent.removeChild(this);
}

It removes the alienship off the screen. But how can I have a variable that increments on each killing?

Thanks

Chiapa