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Procurement & VendorsGenerated accuracy model review: 2026-05-06

Vendor Price Increase Calculator accuracy and testing

This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.

Formula source

  • New annual cost = (current annual spend * (1 + increase percent / 100) + new recurring fees) * (1 - retained discount percent / 100). Annual increase = new annual cost - current annual spend.

Test cases

Default input regression check

Generated from the checked-in default inputs and calculate function.

Inputs

  • Current Annual Spend: $96,000
  • Proposed Increase: 9%
  • New Recurring Fees: 4,000 $/yr
  • Retained Discount: 3%

Expected outputs

  • New Annual Cost: $105,380.80
  • Annual Increase: $9,380.80
  • Net Increase: 9.77%
  • Monthly Budget Impact: $781.73

Known limitations

  • This is a planning tool, not legal, accounting, sourcing, or tax advice. It does not interpret vendor terms, service levels, or contract risk.

Assumptions

  • All pricing, discounts, fees, and contract values are entered by the user.
  • Taxes, foreign exchange, service credits, legal terms, and non-price concessions are not inferred.
  • Inputs are processed locally in the browser and are not stored by this calculator.

Unit handling

  • Current Annual Spend accepts values in $.
  • Proposed Increase accepts values in %.
  • New Recurring Fees accepts values in $/yr.
  • Retained Discount accepts values in %.
  • New Annual Cost is displayed as currency.
  • Annual Increase is displayed as currency.
  • Net Increase is displayed as a percentage.
  • Monthly Budget Impact is displayed as currency.

Rounding rules

  • Number displays use up to 2 decimal places in the calculator UI.
  • Currency outputs are displayed with standard US dollar formatting.
  • Percent outputs are displayed with two decimal places.
  • Input precision follows configured step values where provided.

Version history

1.0.0 - 2026-05-06

Generated accuracy and testing page from the current vendor-price-increase-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for Vendor Price Increase Calculator.

Calculator transparency

Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.

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