=MIN(DATE(YEAR(A21),MONTH(A21)+{4,3},DAY(A21)*{0,1 }))

--
HTH

Bob Phillips

(replace somewhere in email address with gmail if mailing direct)

"kicek" wrote in message
ups.com...
Dear All,
I would like to ask you for help with dates
I have date for example 31-01-2006 and i trying to add 3 months to each
followed date but i have results acordance to preeceding convention

Expected date should be 30-04-2006 but my date is 01-05-2006.
I would like to change the preceeding or following results depend on
other informations


Best regards
Jarek