<P> Fifteen of the 50 largest local police departments employed fewer full - time sworn personnel in 2008 than in 2004 . The largest declines were in Detroit (36%), Memphis (23%), New Orleans (13%), and San Francisco (10%). </P> <P> Ten of the 50 largest local police departments reported double - digit increases in sworn personnel from 2004 to 2008 . The largest increases were in Phoenix (19%), Prince George's County (Maryland) (17%), Dallas (15%), and Fort Worth (14%). </P> <P> Salary varies widely for police officers, with most being among the top third of wage - earners, age 25 or older, nationwide . In May 2012, the overall median was $56,980 . The top 10% earned more than $93,450 and bottom 10% less than $33,060 . </P> <P> The median wages for police and detective occupations in May 2012 were as follows: </P>

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