"Ron Rosenfeld" wrote:
As joeu as pointed out, this is a difficult problem. Here is another
solution:
[....]
=--(RIGHT(A1,3) &" 1, " &LEFT(A1,FIND("-",A1)-1)+2000)

Well, if we're going to make the assumption that all dates are in the year
2000 or later, it is not difficult at all to provide a region-independent
solution.

Since we're making unsubstantiated assumptions, let's assume the dates are
in the years 2001 through 2028.

Then the following should work, assuming that yy-mmm data are already input
and interpreted as dd-mmm of the current year (i.e. numeric Excel dates; the
display format does not matter).

Enter the following formula into X1 and copy down through X1000:

=DATE(2000+DAY(A1),MONTH(A1),1)

Copy X1:X1000 and use paste-special-value to overwrite A1:A1000. Delete
X1:X1000. Format A1:A1000 any way you wish.