I probably did not explain very clearly.  The report says that in 1997
62.4% of mothers initiated breastfeeding in the hospital.  At six months
41.7% of them were still breastfeeding - Ross defines this as the 6
Months Duration percent.  The third statistic is called the percent at 6
months and refers to the number of women from the universe of women
giving birth that are still breastfeeding at six months.  In 1997 that rate
was 26%.  Marsha Walker discussed this at the ILCA conference.
Perhaps she can explain it better than I can.

Ann Twiggs, RD, LD, IBCLC
Working in WIC to Change the World
Columbus, Ohio  (the heart of it all) USA