As you can see, the MLB has consistently maintained a greater disparity in payrolls than the NBA and NFL since the start of the previous decade, and the NHL since 2005. Far more interesting are the trends of salary disparities in the non-baseball leagues. Before the 2004-05 lockout season, the NHL was maintaining a level of payroll inequality similar to that of the MLB. Pro basketball has also seen payroll inequality wax and wane through time, while the NFL's distribution of salaries remains rather stable.
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