Parametric Crop Insurance Product Development

an open case study published by InRisk Labs that i picked up and built out end to end. the brief was to design a parametric insurance product on climate data; i took it past a first percentile-based version into a full actuarial-grade build for soybean farmers in the Indore block of Madhya Pradesh.

the peril is excess rain during the october harvest, a few days of heavy rain on the mature crop wipes out the season through sprouting, discolouration and waterlogging. the cover pays out automatically when an objective rainfall index breaches a trigger, settling in days instead of the slow, subjective claims process of traditional indemnity insurance.

how it’s built

the index is the maximum 5-day rolling rainfall over the october window, area-averaged across the ERA5-Land grid. the work runs as an actuarial control cycle rather than a one-off model:

• data and EVT - detrend for non-stationarity (Mann-Kendall) and model the tail with GEV (block maxima) and GPD (peaks-over-threshold), so triggers sit on return levels, not arbitrary percentiles.
• triggers and dependence - an agronomic damage function links rainfall to loss, with copulas capturing the upper-tail dependence (Gumbel, λ_U ≈ 0.55) that a Gaussian model would miss, and a basis-risk scorecard (~97% policyholder satisfaction).
• pricing and capital - Monte-Carlo pure premium, VaR/CVaR for the Solvency II SCR, plus cost-of-capital and ambiguity loadings on top.
• reserving and regulation - exposure-based UPR, IFRS 17 (PAA + CSM) treatment, and a structure aimed at IRDAI filing, with settlement expressed as a deterministic smart contract.

what it found

priced from the hazard, the pure risk premium (~8.2%) comes out above the legacy 5% rate, the old product was under-priced for the protection it nominally offered. the final term sheet has three payout tiers (1-in-5, 1-in-10, 1-in-20 events) on a ₹50,000-per-acre sum insured. capital required is large (~83% of sum insured) because block-wide weather risk is systemic and doesn’t diversify, which is exactly why reinsurance matters here.