Motion easing changes symbol dimensions

[maguskrool]

I'm trying to create a prototype for an animation for a simple preloader. I'm using a line that grows from one side of the screen to the other (1000px wide). I drew the line, created enough frames for the animation, then selected the frames and created a motion tween. On the first frame I made the line's width 0px and on the last I made it 1000px. So far, so good.

Then I selected the frames and added easing (100 out). This changed the dimensions from 1000px to 1009px... I understand this probably makes the animation smoother, but, well, I want my 1000px, not 1009px.

Anyone ever encountered this problem? Thanks.

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