when i spray my target rate and the applied rate match exactly (i.e. 15 gpa and 15 gpa) , but if i click on the home page it will say (for example) 14.4 gpa when the other screen says 15 and 15. (i hope this is explaining clearly) why dont the 2 match? the applied acres seems correct, but there can be small differences in how the sprayer is filled.