WITH
forgottenCounts AS (SELECT COUNTIF(reviewMarking=“forgotten”) AS forgottenCount FROM `logs.reviews` WHERE reviewCount=1 AND cardID IN (SELECT cardID FROM `logs.latestEssaysCards` WHERE essayName=“qcvc”) GROUP BY userID HAVING COUNT(*) >= 103)
SELECT APPROX_QUANTILES(forgottenCount, 10) from forgottenCounts