Excel: Condense multiples into first occurrence only

Is there a way to take the first occurrence in every value change in a column and re-write it with another value in the same row? For example:

Column 1 Column 2 Column 6 Column 7
apple a apple a
apple a pear a
apple a orange b
pear a grape a
pear a banana b
orange b apple b
grape a orange a
grape a
banana b
apple b
apple b
orange a

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This thread is current as of February 19, 2014.

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