Widget shows wrong delta

[xamrex]

My readings are not every 5 mins, so I supposed it might cause issue, but:

In xDrip+ app, delta shows correct value (it shows value of BG changing within 5 mins.)

1)reading on 16:46 shows 124.5
2)reading on 16:53 shows 112.2
Delta is correct (124.5-112.2) / 7mins * 5 mins = about -8.8

But on widget, that I got on main screen, delta shows wrong value -12.3 (so its just subtract 124.5 - 112.2).
So it just shows difference between actual and previous reading.

Can it be fixed, to show on widget how BG change within 5mins? (so same value like is in app)