Perhaps try this revised formula in K37 first:

=IF(OR(A43="",G37=""),"",IF(G37<TODAY()-90,"Expired",IF(AND(G37<TODAY(),G37
=TODAY()-90),IF(DATEDIF(A43,TODAY(),"y")<40,DATE(YEAR(G37+3 65),MONTH(G37+365
)+1,1),DATE(YEAR(G37+365/2),MONTH(G37+365/2)+1,1)),IF(AND(G37TODAY()+90,DAT
EDIF(A43,G37,"y")<40),DATE(YEAR(G37+365),MONTH(G37 +365)+1,1),DATE(YEAR(G37+3
65/2),MONTH(G37+365/2)+1,1)))))

Test it out with a couple of sample values in A43 and G37
(or just copy down, if you have corresponding values down from A43 and G37),
and see whether all the returns match the expected results .. (think the
returns should be closer now <g)
--
Rgds
Max
xl 97
---
GMT+8, 1° 22' N 103° 45' E
xdemechanik <atyahoo<dotcom
----
"Kane" wrote in message
...
Max
I copied the formula as given, cells as stated, and I get "Expired" for
all
dates.
Example would be (m/d/y)
Birthdate A43 .... 08/08/1960
Issue date G37 .... 10/20/2004
This should give me a new Due date of 05/01/2005
If the certificate is renewed within 90 days of the due date, the new Due
date is extended to the 1st day of the 13th month of the previous Due
date.
I could send you a sample of what I am looking for if that would help

.... Tks Wayne