I am trying to use named ranges in an array formula and it won't work. Below
is the current array formula as entered in cell E8.

{=D8+SUM((Replacements!$C$3:$C$15="NE-777-IUC")*(Replacements!$K$3:$K$15="March")*Replacemen ts!$N$3:$N$15)}


Following are the named ranges from another worksheet withing the same
workbook.
Name range for Column $C$3:$C15 = RBU
Name range for column $K$3:$K$15=RMO
Name range for Column $N$3:$K$15=RLeas

How would I rewrite the array formula to use only the named ranges? Any
help will be greatly appreciated.

TIA
Jan