Absence Rates Project Time (Team) Calculator Examples
Worked examples showing how team size, project workload, absence rates, and working weeks affect estimated project duration.
These examples use the same workload-and-capacity method as the calculator. They show how absence assumptions change average team availability, working-day duration, and the schedule allowance to consider.
Small project with low expected absence
A 90 person-day internal process improvement project is assigned to three full-time people. The team expects 3% of planned time to be unavailable.
Input Summary
Project workload
90 person-days
Team size
3 people
Expected absence rate
3%
Working days per week
5 days
Calculation Breakdown
- 1Full-attendance duration90 / 330.0 working days
- 2Effective team capacity3 * (1 - 3 / 100)2.91 people
- 3Adjusted duration90 / 2.9130.9 working days
- 4Adjusted working weeks30.9 / 56.2 working weeks
Result Summary
Adjusted working weeks
6.2 working weeks
Absence Rates Project Time (Team) Calculator
The project is estimated to take 30.9 working days instead of 30.0, an extension of about 0.9 working days.
Five-person delivery team with 6% absence
A five-person team has a 300 person-day workload and expects a 6% absence rate across a five-day workweek.
Input Summary
Project workload
300 person-days
Team size
5 people
Expected absence rate
6%
Working days per week
5 days
Calculation Breakdown
- 1Full-attendance duration300 / 560.0 working days
- 2Effective team capacity5 * (1 - 6 / 100)4.70 people
- 3Adjusted duration300 / 4.7063.8 working days
- 4Schedule extension63.8 - 60.03.8 working days
- 5Lost capacity allowance300 * 6 / 9419.1 person-days
Result Summary
Lost capacity allowance
19.1 person-days
Absence Rates Project Time (Team) Calculator
The adjusted estimate is 63.8 working days, or 12.8 working weeks, with 3.8 extra working days allowed for absence.
Larger team with a high absence assumption
A 1,200 person-day rollout is assigned to 12 people. The planning assumption is 12% absence and the project works five days each week.
Input Summary
Project workload
1,200 person-days
Team size
12 people
Expected absence rate
12%
Working days per week
5 days
Calculation Breakdown
- 1Full-attendance duration1200 / 12100.0 working days
- 2Effective team capacity12 * (1 - 12 / 100)10.56 people
- 3Adjusted duration1200 / 10.56113.6 working days
- 4Schedule extension113.6 - 100.013.6 working days
- 5Adjusted working weeks113.6 / 522.7 working weeks
Result Summary
Adjusted working weeks
22.7 working weeks
Absence Rates Project Time (Team) Calculator
Allow about 113.6 working days rather than 100.0 working days, a schedule extension of 13.6 working days.
Four-day workweek project
A 160 person-day project has four assigned people, an expected absence rate of 8%, and four project working days per week.
Input Summary
Project workload
160 person-days
Team size
4 people
Expected absence rate
8%
Working days per week
4 days
Calculation Breakdown
- 1Full-attendance duration160 / 440.0 working days
- 2Effective team capacity4 * (1 - 8 / 100)3.68 people
- 3Adjusted duration160 / 3.6843.5 working days
- 4Adjusted working weeks43.5 / 410.9 working weeks
Result Summary
Adjusted working weeks
10.9 working weeks
Absence Rates Project Time (Team) Calculator
The project is estimated at 43.5 working days, or 10.9 four-day working weeks, rather than 40.0 working days.
How to Read Your Results
Adjusted working days estimate the time needed to complete the stated workload after expected absence is included.
The schedule extension is the difference between the adjusted duration and the full-attendance plan.
Effective team size is an average full-time-equivalent capacity, not a prediction of who will be absent on a particular day.
Working weeks are based only on the working-days-per-week input and do not include weekends or public holidays.
Lost person-days represent capacity allowance, not necessarily a continuous block of time or a single person’s absence.
Assumptions & Important Notes
- The workload is expressed consistently in person-days.
- All assigned people have similar availability and productive contribution on average.
- The stated absence rate applies throughout the project period.
- The work can be redistributed among available team members without major delay.
Related Examples
Frequently Asked Questions
How do I choose an absence rate for a project example?
Use a relevant historical average or a documented planning assumption. Make sure planned leave is not counted twice if it is already excluded from capacity.
Can I use decimal team sizes in these examples?
The calculator accepts a team size input, but a decimal value should represent a full-time-equivalent average, such as combined partial allocations.
Why do some examples show more weeks without more working days?
The number of weeks depends on the working days per week. A four-day workweek converts the same working-day duration into more working weeks than a five-day workweek.
Does a larger team always reduce the risk from absence?
A larger team increases average capacity, but it may not protect critical tasks if knowledge or responsibilities are concentrated in a few people.
Should I round the result before planning?
Keep decimals while comparing scenarios, then apply an appropriate practical rounding approach for the project’s scheduling process.
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