How do I set scale to Y position

I was trying to create a sense of depth recently, by setting the scale of an object to it's Y coordinates (as it reaches the top of the screen it gets bigger and visa versa), but I was pretty unsuccessful lol. Can someone help me get on the right track?

Thanks in advanced!

depth is hard to do, but I think the best way would be creating animation using sprites, visually would be much better than so could apply some other effects like shadow eg

Well, this would be an object that you could touch, I wanted to be able to flick it away and have it get smaller as it goes to the bottom of the screen.

You can try to define a maximum size (MaxSize) and a minimum size (MinSize) for your sprites. Then you change the size inversely proportional to the position on the Y axis with MaxSize and MinSize as higher and lower limits

(I do not know if I am understandable , difficult to translate it into English)

I will experiment with that, thanks!