TIME ACCOUNT
Translate two schedules into goal progress without confusing people-time and clock-time
For partners building a move plan, creative project, home system, or other countable outcome, this model estimates progress from two separate weekly hour commitments. Overlap is removed only from elapsed clock time, never from contributed person-hours. The result is a capacity estimate, not proof of productivity or fairness.
| Layer | Periods | Rate or share | Total | Unit |
|---|
Detailed calculation process
Formula, declared symbols, substitutions, intermediate results, and reconciliation
P = W(hA + hB); C = W(hA + hB − o); Q = Q0 + P·u·r
The calculation totals both partners’ person-hours, subtracts simultaneous work only from shared clock-hours, applies a usable-work fraction, and converts usable effort into accepted goal units.
| Symbol | Meaning | Unit / default |
|---|---|---|
| P, C | total person-hours; shared elapsed clock-hours | hours |
| W, hA, hB, o | working weeks; A and B weekly hours; simultaneous weekly hours | 12 weeks; 6, 4, 2 h/week |
| u, r | usable fraction; accepted units per person-hour | 0.80; 2 units/hour |
| Q0, QT | accepted units already complete; target units | 40; 240 units |
- Convert 80% to the decimal usable fraction u=0.80.
- Person-hours: P=12×(6+4)=120 hours.
- Elapsed shared time: C=12×(6+4−2)=96 hours.
- Usable labor: Pu=120×0.80=96 hours.
- New accepted output: 96×2=192 units; projected total Q=40+192=232 units.
- Final reconciliation: 240−232=8 units remaining, while 232−240=−8 confirms no positive headroom.
How to use the time account
- Define a unit that both partners can verify.
- Count only accepted units already complete.
- Record each person’s realistic weekly work hours.
- Identify hours worked simultaneously.
- Estimate usable share from rework records.
- Compare remaining units with the decision date.
Five foundations
Person-hour
One person working for one hour.
Clock-hour
One elapsed hour regardless of headcount.
Overlap
Time both partners are active simultaneously.
Usable effort
Recorded effort left after coordination and rework.
Throughput
Accepted units produced per person-hour.
Three interpretation traps
Parallel work
Overlap saves clock time only when both work streams can proceed independently.
Learning curves
A historical rate may understate early ramp-up or overstate later complexity.
Invisible coordination
Planning, handoffs, and conflict repair belong in the usable-share deduction.
Evidence and interpretation
Use time logs, accepted task counts, and a stable unit definition from a comparable project window. A high projection means the arithmetic capacity is ample; zero progress means the usable share or time is zero; a remaining gap means scope, schedule, or capacity must change.
Limits
- No task dependencies or specialist bottlenecks.
- Constant throughput and usable share.
- No quality weighting between units.
- No inference about fairness or emotional labor.
- Forecast arithmetic is not measured future performance.
Glossary
- Accepted unit
- Work that meets the frozen done rule.
- Capacity gap
- Target units still unsupported.
- Headroom
- Projected units beyond target.
- Rework
- Time spent correcting prior output.
- Parallelism
- Work streams progressing at once.
- Handoff
- Transfer of work or information.
Two cases
Workshop launch: partners reduce scope when 8 units remain unsupported.
Home archive: one partner works alone on scanning while both overlap for labeling, so clock-hours remain below person-hours.
Important note
Do not use the output alone to assign blame, payment, ownership, or household obligations. Review actual work and context together.
Result interpretation
Read labor capacity and elapsed time as two different answers
A projection below the target identifies an arithmetic capacity gap, not a failed relationship commitment. Compare the 8-unit default gap with the 96 usable person-hours: the shortfall can be closed by increasing usable time, improving evidenced throughput, extending the horizon, or reducing scope. Shared clock-hours answer how much calendar time is occupied; person-hours answer how much combined labor is consumed.
Decision and sensitivity
Test the weakest assumption before asking for more time
One additional weekly person-hour adds 12×0.80×2=19.2 projected units under the defaults. A five-percentage-point usable-share change moves output by 120×0.05×2=12 units. Because both exceed the default gap, verify rework and coordination records before extending the deadline; if throughput varies by task class, split the ledger instead of averaging.
Questions
Are overlapping hours double-counted?
They count once for each person in person-hours but once on the shared clock. This distinction matters when two independent tasks happen simultaneously: contributed effort increases twice as fast as elapsed time.
Is a person-hour the same as elapsed time?
No. Two people working together for one hour create two person-hours and one clock-hour. The model reports both so a calendar promise is not confused with total labor.
How should throughput be measured?
Use completed, accepted units divided by recorded person-hours from a comparable period. Exclude rejected output and document any material change in tools or task difficulty.
What does zero usable share mean?
It models no deliverable progress even if time is reserved. Use it to expose a blocked period, not as a judgment about either partner.
Can this decide whether contributions are fair?
No. It describes workload arithmetic, not relationship equity. Care work, coordination, unequal constraints, and quality differences require a separate discussion.
When should the model be replaced?
Use a task network when work is sequential, specialized, or blocked by dependencies. A single throughput rate is not credible when only one partner can perform a governing task.
What if overlap exceeds one partner’s weekly hours?
That input is internally inconsistent because simultaneous time cannot exceed either person’s available time. Reduce overlap to the smaller weekly commitment before relying on the clock-hour result.
How often should usable share be revised?
Re-estimate it after a completed review period or whenever rework, handoffs, or tools materially change. Keep the old value with its observation dates for comparison.
Should the target include stretch work?
Only if stretch work uses the same accepted-unit definition. Otherwise keep the committed target and optional work as separate ledgers so headroom remains interpretable.
How do holidays or missed weeks enter the model?
Lower the planning horizon or weekly commitments to reflect the actual working calendar. The calculator assumes every entered week has the declared availability.