PostgreSQL 9.2.4 - please assist with the query

Hi

I need help, I need to change every result with x being 71008 to be 71007
in the select query below.

SELECT x, sum( value ) as value from table where ……..

Results will show as follows but if the query finds x as 71008 then it must
make it 71007 instead. Is this possible?

71015 | 101240.00

71008 | -19351.34

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