Nancy - The annual UNICEF publication "The State of the World's Children"
gives the info you want in very useful tables at the back, percentage of
children who are exclusively breastfed O-3 months, breastfed with
complementary foods 6-9 months and still breastfeeding 2O-23 months for 145
countries.  Unfortunately I don't have the l996 issue, but the l995 version
shows BLANK spaces for all the countries showing the lowest rates for
under-5 mortality, including the US and Australia - I wonder why?  Perhaps
your local UNICEF would be able to help with the numbers you want.

Pamela, Zimbabwe