Starting from your current query, you can just use
SELECT COALESCE(ROLE, 'Summary') ROLE, COUNT(*) AS cases, SUM(CASE WHEN PREPARED = 'Y' THEN 1 ELSE 0 END) AS prepped, AVG(CASE WHEN PREPARED = 'Y' THEN 1 ELSE 0 END) AS ratio_completed FROM ...
This returns a numeric between
1. You can replace
THEN 1 with
THEN 100 if you prefer a percentage (between
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