Calculate lost work day rate from lost days and hours worked, or find total lost work days from cases and average time lost per case.

A lost-day severity rate counts days, not incident cases. Use one reporting policy and period. Hour/day conversion below means 24 hours per day, not an 8-hour shift.

Lost Work Day Formula

The following formula is used to calculate the lost work day rate for a given number of lost work days and total number of hours worked.

R = (D / H) × 200000

Variables:

  • R is lost days per 200,000 employee hours (the default reporting base)
  • D is the number of lost work days
  • H is the total number of hours worked

To calculate the lost work day rate, divide the number of lost work days by the total number of hours worked. Multiply the result by 200,000 to get the rate.

What is a Lost Work Day?

Lost time measures absence under the chosen reporting policy. Calendar days away and scheduled workdays lost are different measures. This calculator divides total lost days by actual employee hours to estimate a severity rate, or multiplies cases by average lost time. It is not a case-incidence or DART rate. Its hour/day conversions use 24 hours per day, not one work shift; compare only consistent definitions and reporting periods.

How to Calculate Lost Work Day?

The following steps outline how to calculate the Lost Work Day Rate.

  1. First, determine the number of lost work days (D).
  2. Next, determine the total number of hours worked (H).
  3. Next, calculate the lost work day rate using the formula R = (D / H) * 200000.
  4. Finally, calculate the Lost Work Day Rate.
  5. After inserting the values and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Number of lost work days (D) = 10

Total number of hours worked (H) = 50000