Height and Y values ​​changed to .5 in storyboard

Question

I am working on an iOS project in Xcode (7.3) with my colleague. Recently, we noticed a strange thing happening in the storyboard files.

Each time my colleague — let him call Eric — opens the storyboard file, some values ​​of the y elements and the height of the UI increase by 0.5.

Example

Right in front of Eric:

<rect key="frame" x="0.0" y="0.0" width="527" height="43"/> 

Rect post Entrance to Eric:

 <rect key="frame" x="0.0" y="0.0" width="527" height="43.5"/> 

This is not a biggie, but it causes an unsuccessful diff in git every time we open the storyboard file.

Do you know what we can do to prevent this from happening?