Using SUMIF to calculate SUM over 30, 90, 365 day period

**c208b** · 10-07-2008, 09:50 AM

I have a logbook which already uses a number of SUMIF formulas but have been trying to create one so that totals the number of hours flown in the above mentioned periods.

Basically I am attempting to copy the formula and then modify for the relevant column in this case:

=SUM(IF(FlightDates<(TODAY()-90), 0, FlightLength))

FlightDates is the named range of the calender date in column A and FlightLength is the named range for total flying in column Z.

However even though this forumla works in another situation e.g. tracking number of landings in the last 90 days, it comes up with an error.

Any ideas?

Cheers,
c208b

**martesoft** · 10-07-2008, 09:53 AM

This is an array formula, so you need to enter it with Ctrl-Shift-Enter, not simply Enter.

**daddylonglegs** · 10-07-2008, 10:17 AM

That formula will total flightlengths for flights older than 90 days, if you want to total flightlengths within the last 90 days then you'll need to reverse the <

...or use SUMPRODUCT, e.g.

=SUMPRODUCT(--(FlightDates>TODAY()-90),FlightLength)

**c208b** · 10-07-2008, 08:37 PM

daddylonglegs, that it so much simpler and it works a charm, thanks so much.

Cheers,
c20b

**browne3000** · 01-12-2012, 07:05 PM

Hi Dadddylonglegs,

I tried your formulas above wanting the same result but it seems to be adding all the data in the respective range(column), not just the last 7 days, any idea what I'm doing wrong?? here's my formula :

=SUM(IF(flightdates<(TODAY()-6), 0, dailyflyinghours))

thanks