I am trying to set up a formula for a vendor list. Each vendor has its own
individual number in column C.Some of vendors are grouped together. If vendor
is not grouped Column D has same number as of C. If Vendor is grouped, first
vendor number in Column C is assigned to all the group members. I need to set
up a formula so that col. E will look for vendor number in col. D and add
data for one group. Please help. Below is an example of my data list

Vendor name vendor number grouping number Purchases Sales Profit
abcd 251 251 $$$
$$$
addd 233 233
adfg 544 233

251 vendor number has its only one row
233 is grouped and 544 is member of 233 group