=INDEX($A$2:$A$11,MATCH(0,COUNTIF(B$2:B2,$A$2:$A$11),0))
It assumes your list is in Column A, ranging from A2:A11, and your unique values list is in column B. Put the above formula in cell [b]B3.
In cell B2[/b], put:
[pre][code]=$A$2
=INDEX(List6, MATCH(MIN(IF(ISBLANK(List6)+COUNTIF(C$79:$C79, List6), "", IF(ISNUMBER(List6), COUNTIF(List6, "<"&List6), COUNTIF(List6, "<"&List6)+SUM(IF(ISNUMBER(List6), 1, 0))+1))), IF(ISBLANK(List6)+COUNTIF(C$79:$C79, List6), "", IF(ISNUMBER(List6), COUNTIF(List6, "<"&List6), COUNTIF(List6, "<"&List6)+SUM(IF(ISNUMBER(List6), 1, 0))+1)), 0))