excel - Find distinct values based upon multiple columns -

i have spreadsheet of sales (to keep example simple) 3 columns

name -- state -- country  

it's easy find how many sales. (sum lines) can find out how many customers have how finding out how many customers particular state (and country)

name -- state -- country p1----- ca------ usa p2----- ca------ usa p1----- ca------ usa p1----- ca------ usa p3----- ny------ usa p3----- ny------ usa 

the above example give 2 unique customers ca , 1 unique customer ny , 3 usa

edit:

the desired result above table

state - unique customers  ca ----  2 ny ----  1  country - unique customers usa ---- 3 

assuming data have headers in row 1 of columns a, b, , c, follow these directions.

in cell f1 enter state.

in cell g1 enter count.

in cell f2 enter array-formula (must confirmed ctrl+shift+enter↵):

=iferror(index(b$2:index(b:b,counta(b:b)),match(0,countif(f$1:f1,b$2:index(b:b,counta(b:b))),)),"") 

in cell g2 enter regular formula (confirmed enter):

=if(len(f2),countif(b2:b13,f2),"") 

select f2:g2 , copy.

now select f3:f51 , paste.

update

the nature of question changed. first formula same before. gets distinct states in source data , culls them display no blanks.

the second formula different. needs count number of distinct customers in each state, , array formula confirmed ctrl+shift+enter↵).

=if(len(f2),sum(if(f2=$b$2:$b$50,1/(countifs($b$2:$b$50,f2,$a$2:$a$50,$a$2:$a$50)),)),"")