The Bureau of Labor Statistics is expanding its wage survey to include detailed data on pay rates in hundreds of cities. Instead of simply reporting the national average salary for a secretary in a particular industry, for example, the new information will report wage levels across all industries and in 300 cities.

Here are a few revelations for 1997:

• The average pay for a janitor in Kokomo, Ind., is $29,170 -- more than double the amount in Wichita Falls, Texas.

• Lawyers in Los Angeles average $83,500 a year -- besting their colleagues in Philadelphia who only bring in $75,910.

• Physicists and astronomers in Los Angeles bring in $73,440 -- ahead of their New York counterparts, who make $67,110.

• Chicago dentists make $83,890 -- but those in Washington state pull in $91,020.

The bureau cautions that its survey only covers employees who get regular paychecks, with taxes withheld, and qualify for unemployment insurance. This eliminates a whole army of workers -- including business owners, partners, the self-employed and day laborers. That would exclude most well-paid lawyers and investment bankers, who are usually regarded as partners.

Another concern is that some figures are based on a rather low response rate by those surveyed.

Source: Louis Uchitelle and Karl Russell, "Butcher, Baker, Skyscraper Maker: What America Earns," New York Times, September 5, 1999.