BPM's in database

Hi all,

I have just imported all my music into rekordbox after warping most of it. However after warping alot of my tracks still still seem to just be shy of the 128bpm i set. Some are like 128.01, some 127.9 and some more 128.32. But the most part the tracks are 128. 

I have done this in normal mode? Anything i may of done wrong when warping or something i can do in program?

Thanks

Tim