Excel's Formula - sisman

206
Part II: Using Functions in Your Formulas
See Chapter 14 for more information about array constants.
Conditional Sums Using a Single Criterion
Often, you need to calculate a conditional sum. With a conditional sum, values in a range that
meet one or more conditions are included in the sum. This section presents examples of conditional
summing using a single criterion.
The SUMIF function is very useful for single-criterion sum formulas. The SUMIF function takes
three arguments:
range: The range containing the values that determine whether to include a particular
cell in the sum.
criteria: An expression that determines whether to include a particular cell in the sum.
sum_range: Optional. The range that contains the cells that you want to sum. If you omit
this argument, the function uses the range specified in the first argument.
The examples that follow demonstrate the use of the SUMIF function. These formulas are based
on the worksheet shown in Figure 7-15, set up to track invoices. Column F contains a formula that
subtracts the date in column E from the date in column D. A negative number in column F indicates
a past-due payment. The worksheet uses named ranges that correspond to the labels in
row 1. Various summing formulas begin in row 15.
Figure 7-15: A negative value in column F indicates a past-due payment.
All the examples in this section also appear on the companion CD-ROM in the file
named conditional summing.xlsx.