How do I make my character stay still during animation

I have my character going through a series of 8 frames for his animations. However, the character is moving slightly downward every frame, and then jumps back to his original position once the animation loops, and he slides back down again and jumps back infinitely. Is there some sort of origin I have to set for each frame or something to have it not move?

look at your origin points for each frame by using the second to bottom icon on the left of the image editor

I tried that, but it still wants to move all around. The animations are all the exact same size and have the exact same origin.

It would greatly speed up the possibility of help if you added your .capx.