internal storage - Microsoft apps always eating up space with data, for apparently no reason

Microsoft apps (Excel, PowerPoint, Word) use up space apparently for no reason. At this point, I do not use them. I am using a Samsung J7 with Android 6, with 16Gb internal storage and no SD card.

Since I often run out of space, I check which apps are using it. I always find Microsoft apps are taking up space for data, and this seems strange to me.

For instance, I go to Settings -> Applications -> Application Manager -> Word -> Storage, and I see:

Total 256 MB
App 104 MB
Data 152 MB

Why would Word use 152 MB of Data, if I did not read/use any?
I hit CLEAR DATA not long ago, and I checked that the corresponding storage space was actually freed to 0 MB. Now it is taking again 152 MB.

What are those data?
It is not that much space, but in my case it makes a difference.

Excel and PowerPoint behave similarly.

A stranger case seems to be OneNote, with

Total 3.89 MB
App 0 MB
Data 3.89 MB

EDIT: Now, two days after the initial post, Word takes up 16 kB. That is fine. I will check periodically to see when it increases Data size.

EDIT: A couple of months after the initial OP, without using any of the apps, Excel had 251Mb of Data.