The first observance of Labor Day is believed to have been a parade on Sept. 5, 1882, in New York City, probably organized by Peter J. McGuire, a Carpenters and Joiners Union secretary. By 1893, more than half the states were observing a Labor Day on one day or another, and a bill to establish a federal holiday was passed by Congress in 1894. President Grover Cleveland signed the bill soon afterward, designating the first Monday in September as Labor Day.

7.3 million
Number of workers who hold down more than one job. So-called moonlighters comprise 5 percent of the working population. Of these moonlighters, 3.8 million work full time at their primary job and part time at their other job, and about 293,000 work full time at both jobs. See Table 590, 2004-2005 edition,
http://www.census.gov/prod/www/statistical-abstract-04.html.

10.3 million
Number of self-employed workers.
http://www.census.gov/prod/www/statistical-abstract-04.html

20.3 million
Number of female workers in educational, health and social services industries. More women work in this industry group than in any other. Manufacturing was the most popular industry among men, with 11.3 million workers.
http://factfinder.census.gov/servlet/DatasetMainPageServlet?_program=ACS&_lang=en&_ts=133716879923

28%
Percentage of workers 16 or older who work more than 40 hours a week. Eight percent work 60 or more hours a week.
http://www.census.gov/prod/www/statistical-abstract-04.html

15.8 million
Number of labor union members nationwide. About 13 percent of wage and salary workers belong to unions, with New York having among the highest rates of any state, 25 percent. North Carolina has one of the lowest rates, 3 percent.
http://www.census.gov/prod/www/statistical-abstract-04.html.

4.5 million
The number of people who work at home.
http://factfinder.census.gov/servlet/DatasetMainPageServlet?_program=ACS&_lang=en&_ts=133802848315