Hi ,
From what I have understood , the RANK function is the older function.
Excel 2010 has introduced 2 functions which rank viz. the RANK.AVG and the RANK.EQ
Thus , the RANK.EQ function is identical to the older RANK function ; the RANK.AVG does not have an older equivalent.
In the interests of compatibility , Excel 2010 retains the RANK function , though if you are using Excel 2010 , you can use the RANK.EQ function with identical results. If your workbook will be used by those who have Excel 2007 , then you should stick to using RANK.
Narayan