Agriculture, Soil, Fertilizer & Farm Operations calculator

Yield Loss Estimate Calculator

Yield loss percent tells you how much of an expected crop was lost to hail, drought, disease, flooding, or a stand failure, expressed as a share of what the field should have produced. Growers, crop insurance adjusters, and agronomists use it to decide whether to replant, file a claim, apply a rescue treatment, or leave a field to finish. Because most crop insurance and management triggers are written as a percentage, converting raw bushel or ton losses into a loss percent is what actually drives the decision. It also lets you compare damage across fields of different sizes and yield potential on the same scale.

What this calculator does

  • Estimate yield loss percent from lost yield, expected yield, and a target or threshold loss percent.
  • Use it to compare damage, disease, harvest loss, stand loss, drought stress, or storage shrink against a threshold.
  • It computes lost yield as a percentage of expected yield and compares that percent against your action threshold.

Formula used

  • Yield loss percent = lost yield / expected yield x 100

Inputs explained

  • Lost or damaged bushels: Use the same yield unit as the expected yield input.
  • Expected field yield (unaffected basis): Use the planned, appraised, or nearby unaffected yield basis.
  • Insurance or treatment action threshold: Use the farm, crop insurance, harvest, or treatment threshold.

How to use the result

  • Use it right after a damage event or mid-season appraisal, before deciding to replant, treat, or file an insurance claim.
  • It measures gross yield loss only and ignores quality dockage, harvest cost savings on lost acres, and any yield the crop may still recover through compensation.

Current U.S. benchmarks

  • U.S. manufacturing runs at 75.6% of capacity (Federal Reserve, Jun 2026). New factory orders are up 2.3% year over year (Census).
  • Industrial natural gas averages $4.9 per Mcf (EIA, Apr 2026), down 7.7% from a year earlier, with industrial electricity at 8.66 cents per kWh. Process heating and refrigeration budgets track both.

Common questions

  • How do you calculate yield loss percent? Divide lost yield by expected yield and multiply by 100. With 18 bu lost against a 180 bu expected yield, that is 18 / 180 x 100 = 10% loss.
  • What is a good or acceptable yield loss? Anything under your action threshold is generally tolerable. In this example a 5% threshold means the 10% loss is 5 points over the trigger, so it warrants action; single-digit losses below the threshold usually do not justify replanting.
  • Is yield loss the same as a crop insurance claim? No. Yield loss percent is the agronomic starting point, but insurance pays on your covered guarantee and coverage level, so a 10% field loss may or may not exceed your deductible.
  • Should I use planned yield or nearby unaffected yield as the expected value? Use whichever basis your decision hinges on. Adjusters often use an appraised or nearby unaffected strip; a grower planning replant may use the planted-variety yield goal.
  • Why is my loss above threshold negative? A negative points-above-threshold means you are below the trigger. Here the result shows the loss is 5 points over the 5% threshold, so a positive gap signals action is due.

Last reviewed 2026-05-12.