Hi all,

Does anyone have a formula (or formulae) for working out the following:

Don't hesitate to ask me more details, or contact me on MSN...

I have a worksheet with one column showing date and time, in HH:MM (North American Format) and a second column showing temperature readings taken every 15 minutes.

What I am trying to calculate is the total amount of time (in HH:MM) that the temperature was equal to or below a certain threshold.

I have seen some formulaes for calculating elapsed time, but nothing which can account for this variable.

Any help is greatly appreciated and you are guaranteed a free beer should you ever be in Copenhagen!