? subtract ages via birthdate

[whywontthissave]

I need to do some things in Calc that should be simple but are not, and no results are coming up for me. Could someone please advise on how I:

• subtract two dates to get a number of years or an age?
• attach formatting from a date to a gantt chart (e.g. need to color in the cells that correspond to certain date months…)

I’ll start with that. Thanks very much!

[Lupp]

@whywontthissave

… subtract two dates to get a number of years or an age …

This should be simple using DATEDIF().

@whywontthissave

… attach formatting from a date to a gantt chart (e.g. need to color in the cells that correspond to certain date months…)

No clue what you mean.

[EarnestAl]

@whywontthissave

attach formatting from a date to a gantt chart (e.g. need to color in the cells that correspond to certain date months…)

Probably, you want conditional formatting, see Conditional Formatting

[Wanderer]

@whywontthissave

advise on how I:

• subtract two dates

One of the main obstacles is often data wich is not recognized as a date by Calc, because it is imported as text.
.
I usually suggest to change the formatting of your column to number to test: If your dates are not shown different now they are text and have to be converted to numbers first. Afterwards a difference between dates may be as simple as =A2-A1
The numbers you should see are “days since the beginning of the 20th century”. Change format back to date then and remember: Format is NOT changing data, only what is shown to you is changed.

There is a FAQ on converting data:
https://wiki.documentfoundation.org/Faq/Calc/How_to_convert_number_text_to_numeric_data
.
PS: Use DATEDIFF as suggested above, because your question is not simple, when you start to consider leap-years…