Try this in Col C ,,, =IF(A2="TBD","",MATCH(B2,LARGE(IF($A$2:$A$15=A2,$B$2:$B$15),ROW(INDIRECT("1:"&COUNTIF($A$2:$A$15,A2)))),0))
I put TBD into some of the cells in Col A as I don't know what else you would have other than "wait list" in Col A ..... the formula is an array formula, so must be confirmed with control + shift + enter instead of just hitting enter key.