I cannot get a calculation to work. I would like to run a certain report every 4 weeks.

So for example if the week number of the current date is 4 or 8 or 12 etc.

Needs to be ISO calc to work in the uk so 'WeekOfYearFiscal'

How do I do this?

Week of year is not a good choice - unless you want to restart the count at the beginning of year. Try something like =

not Mod ( Div ( Get (CurrentDate) - 1 ; 7 ) ; 4 )

This may need adjustment depending on when you want the cycle to start.

Could you please explain what 'not mod' and 'div' actually do here?

...and I would like it to restart each year.

Div () returns an (arbitrary) absolute number of week; not Mod ( week ; 4 ) returns 1 (True) for every 4th week, 0 (False) otherwise..

If you want to restart each year, try =

not Mod ( WeekOfYearFiscal ( Get (CurrentDate) ; 2 )  ; 4 )

Div () returns an (arbitrary) absolute number of week; not Mod ( week ; 4 ) returns 1 (True) for every 4th week, 0 (False) otherwise..

If you want to restart each year, try =

not Mod ( WeekOfYearFiscal ( Get (CurrentDate) ; 2 )  ; 4 )

That's great, just tried this and it works perfectly.

Out of interest when I have a calc to name a pdf when running a script to save as pdf I want to display the 4 week period number. I currently have

(((WeekOfYearFiscal (DateField))+3) / 4)

which displays 5.25 or 9.25 or 13.25 etc ...instead of the 2, 3, and 4 I am looking for.

Why is this? what have I done wrong?

I currently have

(((WeekOfYearFiscal (DateField))+3) / 4)

which displays 5.25 or 9.25 or 13.25 etc ...

No, that's not possible. What you have is not a valid expression and the only thing it can possibly return is an error.

I want to display the 4 week period number.

Try =

Div ( WeekOfYearFiscal ( DateField ; 2 ) - 1  ; 4 ) + 1