G'day forum,

was hoping someone can help me with with this problem.

My sheet contains 2 columns, id and document:
ID Document
1 doctype1
1 doctype2
2 doctype1
2 doctype2
3 doctype3
4 doctype3
5 doctype1
5 doctype2
How can i count the number of distinct IDs that have a particular set of doctypes?
e.g., 3 IDs have doctype 1 & 2 and 2 IDs have doctype3.
thanks