Try adding all the From dates and all the To dates and then use datedif against
that:

=datedif(sum(q18:t18);sum(q19:t19);"y") & ....

I'm not sure how big those sums have to be before =datedif() breaks, though.



Delya wrote:

Hi,
I need to calculate work experience in years ,months, days. I did a formula
=DATEDIF(Q18;Q19;"y")&" years "&DATEDIF(Q18;Q19;"ym")&" months
"&DATEDIF(Q18;Q19;"md")& "days", where Q18 is 03.09.2007 and Q19 is
05.07.2008. I got a result 0 years 10 months and 2 days. I now want to add up
several such results in order to have total years , months and days, how can
i do it?

--

Dave Peterson