Staffing shortfall and overtime calculator
The roster is short this week. How short, once absence takes its cut, and what does closing the gap cost by overtime against agency cover or borrowed agents? Enter the week's requirement and roster in agent-hours and the calculator gives the shortfall and the options priced side by side.
After expected absence.
- Cost to close by overtime
- £5,654
- Cost to close by agency
- £11,014
- Agents to borrow instead
- 9.8
- Hours expected on the floor
- 1,968.0 h
- Coverage before overtime
- 88.4%
367 agency hours.
Show the working
- Rostered 2050 h less 4% absence = 1968 h expected on the floor, against 2225 h required: 257 h short.
- Overtime: 60 agents × 6 h = 360 h available; 257 h used at £22 = £5654.
- Agency: 257 h ÷ 70% productivity = 367 h at £30 = £11014.
- Borrowing: 257 h ÷ (37.5 × 0.7 productive hours) = 9.8 agents for the week from another team.
Doing this for every interval of the week? Pebble WFM computes the requirement from your forecast and builds the roster. Free month, no card needed.
How the shortfall is calculated
Rostered hours are not the hours you will get: some share will not turn up. Take the expected absence off first, then compare with the requirement. The gap is what needs covering, and it is usually larger than the roster report says.
Overtime is the cheapest cover per hour but it is capped: agents can only work so many extra hours before quality and absence rise, and only some are willing. The calculator applies the cap and shows what it leaves uncovered.
Agency cover costs more per hour and delivers less per hour, so the agency hours needed exceed the gap. Borrowing agents from another team is often the cheapest option of all, and the one that needs a planner to see the whole picture, which is what a workforce management tool is for.
Frequently asked questions
- Should overtime be planned or reactive?
- Planned, in the week before, on the intervals the requirement curve says are short. Reactive overtime on the day covers the interval that already failed. The week planner and schedule efficiency calculator show where the gaps will be.
- Is regular overtime a sign of something?
- Yes: an establishment that is too small for the requirement, or shrinkage that was underestimated. Overtime costing more than a salary every month is a recruitment case.
- What absence figure should I use?
- Your measured unplanned absence for the same week last year, or the absence rate calculator's figure for the team. Three to five per cent is typical; winter runs higher.
Embed this calculator on your site
Paste this where you want the calculator. It stays free and ad-free, updates when we improve it, and the line under it credits the source.
Stop doing this one interval at a time
Pebble WFM forecasts your demand, computes the staffing requirement for every interval, builds the roster and publishes it, with self-service for agents and a copilot that can do what a planner can. Explore a sample organisation on day one.