Normally, the labor force of a country (or other geographic entity) consists of everyone of working age (typically above a certain age (around 14 to 16) and below retirement age who are participating workers, that is people actively employed or looking for work. Child labor laws in the United States forbid employing people under 18 in hazardous jobs.
The fraction of the labor force that is seeking work but cannot find it determines the unemployment rate.
The labor force is the number of people employed and unemployed. Participation rate is the ratio between the labor force and the overall size of their cohort (national population of the same age range). In the West during the latter half of the 20th century, the labor force participation rate increased significantly, largely due to the increasing number of women entering the workplace. Claudia Goldin and others, specifically point that by the mid 1970s there was a period of revolution of women in the labor force brought on by a source of different factors. Women more accurately planned for their future in the work force, investing in more applicable majors in college that prepared them to enter and compete in the labor market. In the United States, the labor force participation rate rose from approximately 59% in 1948 to 66% in 2005 , with participation among women rising from 32% to 59% and participation among men declining from 87% to 73% Conversely, the labor force participation rate can decrease when the rate of growth of the population outweighs that of the employed and unemployed together. The labor force participation rate is a key component in long term economic growth, almost as important as productivity.
Pop = total population
LF = labor force = U + E
LFpop = labor force population
p = participation rate = LF / LFpop
E = number employed
e = rate of employment = E / LF
U = number of unemployed
u = rate of unemployment = U / LF
--The labor force participation rate explains how an increase in the unemployment rate can occur simultaneously with an increase in employment. If a large amount of new workers enter the labor force but only a small fraction become employed, then the increase in the number of unemployed workers can outpace the growth in employment.