Hi Celast
I think the way i would look at it is - is it a downward trend?
80% in target sound great , 2% below even better
the 18% over is what needs looking at. If it was in the earlier stages, research phase - where you find out what is bad for you then worry not, the next month is going to look better if you have been 'eating to your meter'.
However, if these are in the latter stages of the month where you know you shouldnt have something 'but just this once wont hurt' then perhaps a re-think is needed
hope that makes sense
Mary x