Parametric Insurance: Instant-Payout Weather Triggers

Parametric insurance pays a pre-agreed amount when a defined index — wind speed, rainfall, temperature — crosses a threshold, regardless of actual loss. Unlike traditional indemnity insurance, there is no claims adjustment: the trigger fires, the payment is made, often within days. The trade-off is basis risk: the possibility that the index payment does not match actual loss. This guide explains the mechanics, premium construction, and how to quantify basis risk.

How Parametric Triggers Work

IF index_value ≥ trigger_threshold THEN pay fixed_amount
ELSE pay 0

Tiered structure (common for agriculture):
  rainfall < 20mm in 30 days  →  pay 100% of sum insured
  rainfall 20–40mm            →  pay 60% of sum insured
  rainfall > 40mm             →  pay 0

Premium Calculation

Technical premium = Sum insured × Trigger probability × (1 + Loading factor)

Where:
  Trigger probability = Historical frequency of index breaching threshold
  Loading factor      = Typically 30–60% of pure premium

Basis Risk: Quantification

Basis risk has two components:

• Spatial basis risk: The measurement station is not co-located with the insured asset — wind at the station may not equal wind at the farm 30km away.
• Product basis risk: The index parameter does not fully capture all loss drivers.

Correlation (r) between index and actual loss:

r ≥ 0.90   →  Low basis risk (parametric suitable)
r 0.70–0.89 →  Moderate risk (tiered / hybrid structure recommended)
r < 0.70   →  High basis risk (indemnity may be more appropriate)

What-If Scenarios