Question 1

What is the 17c formula?

Accepted Answer

The 17c formula is the diminished-value calculation State Farm popularized following the Georgia Supreme Court's 2001 decision in State Farm v. Mabry (274 Ga. 498), which required insurers to evaluate first-party DV claims. The formula itself is attributed to Infinity Insurance; the name "17c" comes from paragraph 17(c) of the Mabry trial court order. The formula computes: ACV × baseLoss% × damageMultiplier × mileageMultiplier. The 10% base loss cap and the steep mileage multiplier are structural weaknesses — they produce consistently low DV numbers that are defensible-on-paper but understate real post-accident market loss.

Question 2

Why does my insurance use 17c instead of real market data?

Accepted Answer

Because 17c produces low, consistent, easy-to-defend numbers. The formula was adopted nationwide by carriers because it scales: an adjuster can apply 17c to any claim in minutes, and the output is bounded at 10% of pre-loss ACV regardless of how severely the vehicle was damaged. Real market data is harder to defend in the carrier's favor — comparable sales of vehicles with documented collisions routinely show 15-30% market value loss. The counter to 17c is to bring actual comparable-sales evidence.

Question 3

Is the 17c formula fair?

Accepted Answer

No, not for most heavily-damaged vehicles. The three structural problems: (1) the 10% cap is arbitrary and ignores actual market data; (2) the damage multiplier is set by the adjuster based on subjective severity assessment, not on the actual repair invoice; (3) the mileage multiplier penalizes older vehicles whose depreciation already accounts for much of their value reduction, leaving the inherent-DV (post-accident-stigma) component understated. Courts in Georgia, California, and elsewhere have recognized these limitations.

Question 4

How do I counter a 17c-based offer?

Accepted Answer

Bring actual comparable sales. Request the carrier's full market valuation report; it will name the comparable sales they used. Then run a VVA Diminished Value Report ($199.95) that pulls pre-loss and post-repair comps from your ZIP, with mileage and trim adjustments applied transparently. The appraisal clause does NOT require the parties to use 17c — it requires them to determine the actual loss. Bring the comparable-sales evidence; the 17c number stops being the ceiling.

Question 5

What are the standard 17c damage multipliers?

Accepted Answer

Insurers nationwide use a 5-level damage multiplier: severe (1.00) for frame or unibody compromise, major (0.75) for substantial structural repair, moderate (0.50) for multiple panels with some sectioning, minor (0.25) for cosmetic panel work without structural damage, and none (0.00) for purely cosmetic damage with no panel replacement. The mileage multiplier scales linearly from 1.0 at 0 miles to 0.0 at 100,000 miles, reducing by 0.2 per 20K miles.

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