=SI(ESTNA(INDEX('130514 table cadences'!$C$2:$C$6633;EQUIV($A2&"$"&C$1;'130514 table cadences'!$B$2:$B$6633&"$"&'130514 table cadences'!$A$2:$A$6633;0)));"";INDEX('130514 table cadences'!$C$2:$C$6633;EQUIV($A2&"$"&C$1;'130514 table cadences'!$B$2:$B$6633&"$"&'130514 table cadences'!$A$2:$A$6633;0)))