One way to do this is with an index function, assuming that there are no other rows of data on this worksheet other than the group that you're trying to find. Here's an example of a formula that could work for you. It assumes that your data starts in K2 and you want to have your result in K1.
=INDEX(OFFSET(K2,,,ROWS(K:K)-ROW(K2),1),MATCH(9.99999999999999E+307,
OFFSET(K2,,,ROWS(K:K)-ROW(K2),1)),1)
The offset creates an array for all cells below k1 without counting k1. The match function searches for the largest number possible, this formula assumes that you're looking for numbers. If you're looking for text, or a combination, you'll have to use a different formula by replacing the match portion with:
MATCH(REPT("z",255) 'for text
MAX(MATCH(9.99999999999999E+307,range),MATCH(REPT("z",255) 'for numbers and text
Source: http://www.techonthenet.com/excel/questions/last_value.php