Syntax: CSUM(argumentlist, C)
argumentlist = any combination of cells or ranges
C = a constraint expression
CSUM returns the sum of its arguments which satisfy the constraint C. Blank cells and cells containing strings are not counted.
Examples:
CSUM(L1..L3, #5) = 1.32, where L1 = 1.32, L2 = 5.45, and
L3 = 8.32
CSUM(C5..C10, #=D1/D10) = 150, where C1..C10 are 10, 20,
30, 40, 50, and D1 = 100 and D10 = 10
Excel function: N/A