United States
Organization responsible for the statistics
The statistics are collected, compiled and published by the US
Department of Labor, Bureau of Labor Statistics.
Objectives and users
Not available.
Coverage
Strikes and lockouts
The statistics cover:
- constitutional or official strikes
- unofficial or wild-cat strikes
- sympathetic strikes
- revolving or rotating strikes
- general strikes
- work stoppages initiated by employers
- sit-ins
Political strikes, working to rule, go-slows and overtime bans
are not covered.
Minimum threshold
A minimum of 1,000 workers simultaneously involved, with the
stoppage lasting at least a full shift.
Prior to 1982: stoppages involving six employees or more and
lasting at least a full shift.
Economic activities
No particular branches of economic activity or sectors are
excluded.
Workers
Workers directly involved and workers indirectly involved. As
well as regular paid employees, including part-time workers, the
statistics cover temporary, casual and seasonal workers. Workers
laid off, or absent during the stoppage for any other reason
(sick leave, annual leave, etc.) are not included.
No particular occupational groups are excluded.
Geographic areas
Whole country.
Types of data collected
- number of strikes and lockouts
- number of workers involved
- duration
- time not worked
Concepts and definitions
Work stoppage
The temporary cessation of work by a group of employees to
express a grievance or enforce a demand or the temporary
withholding of work by an employer or group of employers to
enforce terms of employment on a group of employees.
This is a working definition for statistical purposes
Methods of measurement
Strikes and lockouts
A strike is recorded as any group of 1,000 or more workers
involved in a work stoppage. The continuation of a strike or
lockout that is interrupted but later resumes still due to the
same case of dispute is treated as a new strike or lockout if the
period of interruption exceeds one work shift.
Work stoppages resulting from the same case of dispute and
occurring simultaneously either in different establishments of
the same enterprises or in establishments of different enterprise
are regarded as one strike or lockout. Those resulting from the
same case of dispute but occurring at different times in
different establishments of the same enterprse or in
establishments of different enterprises are counted as separate
strikes or lockouts.
Workers involved
The number of workers involved is the maximum number of workers
that took part during the course of the stoppage, even if some
workers participated for only part of the duration. Part-time
workers are counted as individuals on the same basis as full-time
workers.
Duration
The duration is measured in straight calendar days from the date
on which the stoppage began in the first economic unit involved
up to the date on which it terminated in the last one.
Time not worked
Total time not worked is measured in workdays, by ascertaining
the total amount of time not worked on each day of the strike and
summing these totals. Time not worked is measured for all
workers involved, whether directly or indirectly. The shorter
working hours of part-time workers are taken into account as
follows: the average number of hours normally worked per day by
part-time employees is multiplied by the number of such employees
and the resulting estimate of time lost is combined with the
estimate for full-time employees. Overtime is not taken into
account.
Classifications
Branch of economic activity
The data are classified by branch of economic activity using the
Standard Industrial Classification system, developed by the
Office of Management and Budget. In the case of a multi-industry
stoppage, workers involved are apportioned according to the
industry in which they are employed.
Reference period and periodicity
The statistics are compiled and published for periods of one
month and one year. The information published on the number of
strikes and lockouts and the number of workers involved refers
only to stoppages beginning during the particular reference
period. The published data on time not worked relate to
stoppages beginning during the reference period plus those
continuing from the previous period.
Analytical measures
The percent of estimated working time lost per month or
year is calculated by dividing the aggregate number of workdays
lost due to stoppages by the aggregate number of workdays
available in the economy, excluding national holidays. This
measure is used for comparing the impact of stoppages on the
economy between different periods.
Historical background of the series
Not available.
Documentation
Series available
Not available.
Bibliographic references
US Department of Labor, Bureau of Labor Statistics: Monthly
Labor Review (monthly);
Idem: Current Wage Developments (monthly);
Idem: Press releases (annual, in February);
Idem: Handbook of Labor Statistics (occasional).
Data published by the ILO
The number of strikes and
lockouts, the number of workers involved, the number of days not worked
and rates of days not worked, by economic activity.
Confidentiality
Not available.
International standards
Not available.
Methods of data collection
There is no legal obligation to report the occurrence of a strike
or lockout. The initial information is obtained from a
nationwide review of general newspapers and union periodicals,
and from the Federal Mediation and Conciliation Service.
Telephone calls are then made to union and management officials
to obtain details. Even if there are no indications of a
stoppage, telephone contact is made with the officials at the
termination of an agreement to determine the outcome of the
negotiations, including possible stoppages.