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Work Stoppages: Calculation

Since 1981, the Work Stoppages program produces monthly data on six time series detailed below.

Number of days idle from work stoppages in effect in period

Total number of days of idleness from all major work stoppages ongoing during the specified month. The days of idleness estimates are calculated by multiplying the duration of the work stoppage (in days) by the number of workers involved in the work stoppage.

For example, if a work stoppage lasted 10 workdays (Monday through Friday, excluding federal holidays), and 4,000 union workers were directly affected, then the duration is multiplied by the total number of workers affected to arrive at 40,000 days of idleness (4,000 X 10 = 40,000). If another work stoppage resulted in 20,000 days of idleness, the days of idleness would be summed together (40,000 + 20,000 = 60,000) for a monthly total of 60,000 days of idleness.

Number of days of idleness from work stoppages in effect as a percentage of total estimated working time

The total number of days of idleness in effect for a specific month divided by the total number of workdays, based on data from the Current Employment Statistics, as published in The Employment Situation news release.

The numerator is the total days of idleness from major work stoppages in effect for a specific month. The denominator is the total number of workdays (in thousands) based on the sum of the nonagriculture plus agriculture employees (from Table B-1 and Table A-8, not seasonally adjusted, in The Employment Situation news release) multiplied by the number of work days (Monday through Friday, excluding federal holidays). The calculation is expressed as a percentage of working time (e.g., 0.01 percent). For the monthly time series, this is expressed as 0.00 percent, with a footnote detailing that the percent is above zero, but below 0.005 and rounded down to 0.00 percent).

For example, if the number of total days of idleness for the month was 60,000 (60 thousand) and the total number of workdays was 3,000,000 workdays (in thousands), then the percentage of total estimated working time would be 60/3,000,000 = 0.002 percent.

This value would be listed as 0.00, with a footnote stating the value was under 0.005 percent. In this example, more than 150 thousand days idle in the month (numerator) would round up to 0.01 percent.

Number of workers involved for stoppages beginning during the month

Total (sum) of the number of workers for major work stoppages beginning in the specified month, rounded to the nearest hundred. This measure identifies the number of workers for new stoppages and is used for determining the number of workers for calendar year annual major work stoppages. Ongoing major work stoppages from a prior month are not included in this measure.

For example, if there are two new major work stoppages (one with 2,000 workers and one with 1,500 workers) and one ongoing stoppage from a prior month with 5,000 workers then the calculation would be 2,000 + 1,500 workers = 3,500 workers. The prior month's 5,000 would be excluded from the calculation.

Number of workers involved in stoppages in effect during the month

Total (sum) of the number of workers for all major work stoppages in effect during the specified month. For example, there are two new major work stoppages and one ongoing major work stoppage from a prior month with 5,500 workers involved (new work stoppages with 2,000 workers and one with 1,500 workers) then the calculation is 5,500 + 2,000 + 1,500 workers = 9,000 workers.

Number of major work stoppages beginning in the month

The number of major work stoppages that began during the specified month. This measure identifies new stoppages and is used for determining annual major work stoppages for the calendar year.

For example, there if are only two new major work stoppages during a month then the events equal two.

Number of major work stoppages in effect during the month

The number of all major work stoppages in effect during the specified month. For example, if there are two new major work stoppages during the month plus one ongoing work stoppage beginning in a prior month then the calculation is 2 + 1 = 3. If in effect major work stoppages were used to identify annual major work stoppages, there would be double counting for annual measures.

Last Modified Date: January 23, 2019