months and days between dates

Tricky... The first problem is the intended result. Months have a varying number of days in them, days and weeks have set values. For example the difference between 1st July and 1st September is 2 months but this does not give an accurate count of the number of days (61).

It would be better to calculate the number of days difference and forget the months.

You would need a lookup table showing a numeric value for each date that would show each date with a day value from a starting point. If your earliest date is 01/01/2000 then that would be day zero. Then using the lookup table calculate the day value for your beginning and end dates. Subtract one from the other to get the number of days.

If all your dates are from this year:

You can create your own Cell Format (call it day of the year) Select the Type: Date & Time
drag the icon for Day of Year into the box and delete the others.

Convert your dates to this new Format, subtract one value from the other to get the number of days difference.

I'm always wondering when I read such a question.
Every iWork program offers a Help menu.

In this one anybody may see several entries:



Will you ask on this forum every time you will need for a function ?

If your first date is stored in D8 and the second stored in E8, looking in the Help would teach you that the difference in months is given in F8 by:
=DATEDIF(D,E,"M")
the difference in days is given in G8 by:
=DATEDIF(D,E,"D")

Please, listen to Bessie Smith and "do your duty" 😉

Yvan KOENIG (from FRANCE mardi 3 février 2009 16:46:56)