Rolling Claims and Loss Ratio Ranking

Write a SQL query using window functions to calculate a rolling 30-day claims count by policyholder and rank regions by loss ratio. Use the policy, policyholder, and claims data, treating the 30-day period as the claim date plus the preceding 29 calendar days. Assume loss ratio equals total claim amount divided by total annual premium.

Output

1. One row per policyholder and claim date with policyholder_name, claim_date, rolling_30_day_claims, region, loss_ratio, and region_rank.
2. Include only policyholders with claims, order by policyholder name and claim date, and rank regions by descending loss ratio with tied regions sharing a rank.