I have a nested function:
=IF(AND(NOT(ISERR(FIND("CH",K2))),MONTH(B2)=3),S2+Spread!E$12,IF(AND(NOT(ISERR(FIND("CK",K2))),MONTH(B2)=5),S2+Spread!E$13,IF(AND(NOT(ISERR(FIND("CN",K2))),MONTH(B2)=7),S2+Spread!E$14,IF(AND(NOT(ISERR(FIND("CU",K2))),MONTH(B2)=9),S2+Spread!E$15...