value: value to look up
vector1: range to search:
vector2: range of return values
If vector1 has more rows than columns, LOOKUP searches the first row of vector1, otherwise the first column. If vector2 is omitted the return value is taken from the last row or column of vector1.
If LOOKUP can't find value it uses the largest value less than value. The data must be sorted. If value is smaller than the first value it returns #N/A. If the corresponding location does not exist in vector2, it returns #N/A.