Examples
Examples
Try the starting example
- Tasks: name, month number from 1, quoted cost $
- Service,1,100 Repair,3,500
- Opening maintenance reserve ($)
- 100
- Months to plan
- 3
- Minimum equal monthly contribution rounded up to US cents ($)
- $166.67
- Total quoted work ($)
- $600.00
- End-of-month reserve balances ($)
- 166.67, 333.34, 0.01
- Closing reserve ($)
- $0.01
Try another scenario
- Tasks: name, month number from 1, quoted cost $
- Service,1,100 Repair,3,500
- Opening maintenance reserve ($)
- 300
- Months to plan
- 3
- Minimum equal monthly contribution rounded up to US cents ($)
- $100.00
- Total quoted work ($)
- $600.00
- End-of-month reserve balances ($)
- 300, 400, 0
- Closing reserve ($)
- $0.00
Calculation method
Calculation method
Minimum equal monthly contribution rounded up to US cents ($)
At each month m require opening reserve + m×contribution ≥ cumulative due costs. Take the largest non-negative prefix requirement, then round contribution up to US cents. Contributions arrive before monthly spending.
Total quoted work ($)
Sum all entered task quotes.
End-of-month reserve balances ($)
Opening reserve + cumulative contributions − cumulative due costs.
Closing reserve ($)
Reserve balance after the final planned month.
Symbols and units
- a
- Tasks: name, month number from 1, quoted cost $
- b
- Opening maintenance reserve ($)
- c
- Months to plan
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- A deterministic reserve schedule using whole-cent amounts and integer-cent accounting, excluding interest, inflation and uncertain work. It assumes the same contribution at the start of every month and no negative opening reserve.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.
Further reading
OpenStax: arithmetic and geometry ↗
Background reading; this does not imply endorsement or independent review of SumFizz.