Hi
As the formula needs to be an array one + you're pulling info. from several columns I would highly recommend you use a Helper column (can be hidden) to avoid re-calculating the matching rows in your Master table:
Blue table is named TBL_MASTER
Created a named var. NbActiveClients with formula: =COUNTIF(TBL_MASTER[Active:],"yes")
In A11:
=IF(ROWS($1:1) > NbActiveClients, "", AGGREGATE(15,6,1/(TBL_MASTER[Active:]="yes")*(ROW(TBL_MASTER[Active:])-ROW(TBL_MASTER[#Headers])),ROWS($1:1)))
Enter only has AGGREATE is a array function
In B11:
=IF([@HELPER]="","",INDEX(TBL_MASTER[Client Name:],$A11))
and copy right
SAMPLE here