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20_044039 ch15.qxp 11/21/06 11:07 AM Page 278
Part II
Working with Formulas and Functions
The LOOKUP function looks in a one-row or one-column range (lookup_vector) for a value (lookup_value)
and returns a value from the same position in a second one-row or one-column range (result_vector).
Values in the lookup_vector must be in ascending order. If lookup_value is smaller than the
CAUTION
CAUTION
smallest value in lookup_vector, LOOKUP returns #N/A.
Figure 15.4 shows the tax table again. This time, the formula in cell B3 uses the LOOKUP function to return
the corresponding tax rate. The formula in cell B3 is
=LOOKUP(B2,D2:D7,F2:F7)
If the values in the first column are not arranged in ascending order, the LOOKUP function may
CAUTION
CAUTION
return an incorrect value.
Note that LOOKUP (as opposed to VLOOKUP) requires two range references (a range to be looked in, and a
range that contains result values). VLOOKUP, on the other hand, uses a single range for the lookup table,
and the third argument determines which column to use for the result. This argument, of course, can con-
sist of a cell reference.
FIGURE 15.4
Using LOOKUP to look up a tax rate.
Combining the MATCH and INDEX functions
The MATCH and INDEX functions are often used together to perform lookups. The MATCH function returns
the relative position of a cell in a range that matches a specified value. The syntax for MATCH is
MATCH(lookup_value,lookup_array,match_type)
The MATCH function’s arguments are as follows:
n lookup_value: The value you want to match in lookup_array. If match_type is 0 and the
lookup_value is text, this argument can include wildcard characters “*” and “?”
n lookup_array: The range being searched.
n match_type: An integer (–1, 0, or 1) that specifies how the match is determined.
NOTE If match_type is 1, MATCH finds the largest value less than or equal to lookup_value.
NOTE
(lookup_array must be in ascending order.) If match_type is 0, MATCH finds the first value
exactly equal to lookup_value. If match_type is –1, MATCH finds the smallest value greater than or equal
to lookup_value. (lookup_array must be in descending order.) If you omit the match_type argument, this
argument is assumed to be 1.

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