Wrong value retrieved after querying in SQ00

Hello,

I have question regarding querying in SQ00 transaction.

when i take a look at retrieved data after querying, there was few wrong value among many retrieved data.

There is a field for days which is filled based on calculation that is Current date - Goods delivered date.
Funny thing is only very few outcomes are wrong among many outcomes. and so far, i couldn't find any patterns and differences between correct outcomes and wrong outcomes. (e.g. there is bigger number and smaller number of days in correct value when i compare correct value with wrong outcomes)

I am trying to find out what i missed since i believe SAP is quite trustworthy.

Can anyone who had similar problem please tell me a solution or advice to figure out my issue.