Scaling Movie Clip Help

[MG_Kobra]

I know how to scale movie clips and graphics on the stage by using motion tween. What I am wanting to know is how to do this using action script. What I am wanting is for the graphics to get bigger or smaller based on where they are on the stage.

I have attached a FLA called "scale_demo" to this post. There is a blue circle and a red square that start down at the bottom and go up to the top as they clip plays. They start out big, but as they go up the stage they get smaller based on how many meters they have moved. As I said before I know how to do this using motion tween, but I prefer to have it done using action script.

If someone could help, it would be very much appreciated.

Thanks