Index match multiple results in drop down

Hi,

I want to use excel drop down that should be populated by Index Match multiple & unique results (dynamically). Currently I can achieve the Unique List by using the array formula

=INDEX(Table1[Category 3],MATCH(0,COUNTIF(INDIRECT({"E1:"}&ADDRESS(ROW()-1,COLUMN(),3),TRUE),Table1[Category 3]),0))

where unique list starts from E2.


The problem with this formula is it does not return array (of unique values). I have to drag down the formula to make it work.

The excel file is attached. Any help will be greatly appreciated.