L.A. County workers’ wallets got fatter in 2004 by nearly 6 percent.

That’s in line with the national average, but nowhere near the boosts workers in Orange County and the Inland Empire saw.

In the latest sign of the strengthening local economy, compensation that is, salaries and benefits in Los Angeles County rose 5.9 percent in 2004, up from 3.3 percent in 2003, according to data just released from the U.S. Bureau of Economic Analysis.

But L.A. lagged the rest of the Southern California region. Orange County posted a 7.9 percent gain, while a population surge and solid job growth pushed Inland Empire compensation packages up 12 percent.

“L.A. is a more mature economy, so it’s only natural the growth rate would be a little slower than in places like the Inland Empire that are still developing,” said Nancy Sidhu, vice president and senior economist with the Los Angeles County Economic Development Corp.

L.A. County employees are still doing well in comparison with their neighbors. The average compensation package in L.A. County totaled $55,017 in 2004. Orange County employees fared slightly better at $55,537 and in Ventura County it was $53,451. San Bernardino and Riverside county workers averaged $43,700 and $42,005, respectively.

The Bureau of Economic Analysis compensation survey is considered a more comprehensive barometer of overall economic health than the state’s monthly payroll survey. The data are culled from income tax withholding data and other forecasts of individual tax returns, so the survey takes in many self-employed and contract workers who file 1099 forms but are not on corporate payrolls. It does not include the “underground economy,” where employees are paid in cash.