Work Stoppages: Description of Measures

Work stoppage data are published monthly and annually, providing information on work stoppages of 1,000 workers or more:

Annual information is available in an annual news release both in paper form and online. It includes the above data for work stoppages of 1,000 workers or more and the historical table.

Reports are compiled from news reports and direct contacts with labor or management representatives.

Uses of this data include: measures of work stoppage activity; trends in collective bargaining; and economic effects of work stoppages.

Work stoppages are strikes or lockouts. A strike is a temporary stoppage of work by a group of employees (not necessarily union members) to express a grievance or enforce a demand. A lockout is a temporary withholding or denial of employment during a labor dispute to enforce terms of employment upon a group of employees. Because of the complexity of most labor-management disputes, BLS makes no attempt to distinguish between strikes and lockouts in its statistics; both types are included in the term "work stoppages" and are used interchangeably. The terms "dispute," "labor-management dispute," and "walkout" are also used interchangeably.

Days of idleness are the aggregate number of work days lost as a result of a work stoppage. It is calculated by multiplying the number of workers involved in the stoppage by the number of days the stoppage is in effect. Aggregate figures are the result of summing all products thus obtained.

Number of workers includes all workers made idle for one shift or longer in establishments directly involved in a stoppage. It includes those who initiate the strike as well as others in the establishment who honor picket lines or are idled because the plant is closed down. Other branches or plants of the struck employer may also be affected, and workers so idled are counted. The data do not account for secondary idleness that is, the effect of a stoppage on other establishments or industries whose employees may be made idle as a result of material or service shortages.

Percent of estimated working time lost is calculated by dividing the days of idleness for the period by the available work days for the period. The available work days for the period is computed by multiplying the average employment for the period by the number of days typically worked by most employed workers during that period. In these computations, Saturdays (when customarily not worked), Sundays, and established Federal holidays are excluded. Also, private household, forestry, and fishery employees are excluded from the average employment data.


Last Modified Date: March 19, 2009