Top Percentile Return Rates by Region

Problem

Table `Returns` holds the return rate of each product line within a sales region: `line_id`, `region`, and `return_rate` (a decimal between 0 and 1, higher is worse). The quality team wants the worst offenders within each region. For every region, find the product lines whose return rate sits in the top 5 percentile of that region, where 'top 5 percentile' means a percent-rank of at most 0.05 when the lines are ranked from highest return rate to lowest within the region.

Return `line_id`, `region`, and `return_rate`, ordered by `region` ascending, then `return_rate` descending, then `line_id` ascending.

Tables

Example rows — the live problem includes the full dataset.

Expected output

Your answer should return 4 rows with the columns line_id, region, return_rate.

Starter code (SQL)

SELECT *
FROM Returns;

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