Growing Degree Days Formula

[jdonnelly333]

All,

I would really love some help. I'm a novice at building formulas, so I'm
looking for some help making a formula for calculating growing degree days.
I've found others on the web, but none that require base low and limit high
temperatures.

ColumnA is Hi temperatures, ColumnB is low temperatures.

Basic degree day calculations are figured by (A1+B1)/2-50. What I need
different is if A1 is greater than 86, I need it to be calculated as 86. If
B1 is less than 50, I need it calculated as 50.

Can anyone help?

 

[Luke M]

Try this:

=(IF(A1>86,86,A1)+IF(B1<50,50,B1))/2-50

 

[James Silverton]

Luke wrote on Thu, 30 Apr 2009 10:11:01 -0700:

Try this:

=(IF(A1>86,86,A1)+IF(B1<50,50,B1))/2-50

Luke M
*Remember to click "yes" if this post helped you!*

"jdonnelly333" wrote:

To the OP: this formula could give negative growing days. What does that
mean?
--

James Silverton
Potomac, Maryland

Email, with obvious alterations: not.jim.silverton.at.verizon.not

 

[jdonnelly333]

Yes, the negative values can be an issue, and leads to my follow-up. If
values are negative, how do you get it to read zero?

 

[James Silverton]

jdonnelly333 wrote on Thu, 30 Apr 2009 10:50:38 -0700:

:

Yes, the negative values can be an issue, and leads to my follow-up.
If values are negative, how do you get it to read zero?

There is more than one way to go, including defining a name or writing a
macro, but I think the easiest way would be to put the value calculated
by the given formula in C1 and have D1 equated to =if(c1>0,c1,0)


--

James Silverton
Potomac, Maryland

Email, with obvious alterations: not.jim.silverton.at.verizon.not