Formula for degree days

[JohnF]

what is the formula in working with degree days where you want to say
subtract degree day that was above zero degrees but will add to a number when
the deegree day is below zero such as -10 degrees.
Thanks

 

[Pete_UK]

Taking this formula:

=Temperature - Degree_day

then if Degree_day is positive (above zero) it will be subtracted, and
if it is negative it will be added.

Hope this helps.

Pete