Diminished Value 17c Worksheet and Formula (pdf)


  Component Calculation Why it’s wrong
1 Base Loss in Value 10% of NADA retail
  • 10% is arbitrary
  • 10% could not logically apply to all cars
  • 10% is too low
  • NADA Retail is for dealers not consumers
2 Mileage Modifier
  • 1 for 0 miles
  • 0 for 100,000 miles
  • Reversly proportional in between
  • Mileage is already a component of NADA retail
  • Mileage used twice
  • No evidence that cars with more than 100K lose no value
  • Arbitrary and illogical
3 Damage Modifier
  • 1 for severe structural damage
  • 0 for no structural damage
  • Proportional in between
  • Does not consider flood damage
  • Does not consider body damage sans structural
  • Does not consider airbag deployment
  • Very subjective

If the insurance company is using 17c to compensate you for your loss in value, say no.

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