WITH 
    AvgPts AS (
        SELECT 
            AVG(POINT * 1.0) AS AVG_PT
        FROM 
            TEST_RESULTS
        WHERE 
            TEST_ID = '100'
    ),
    StdDev AS (
        SELECT 
            SQRT(AVG((POINT * 1.0 - AVG_PT) * (POINT * 1.0 - AVG_PT))) AS SD_PT
        FROM 
            TEST_RESULTS
            CROSS JOIN AvgPts
        WHERE 
            TEST_ID = '100'
    )
SELECT 
    USER_ID AS USER,
    POINT AS PT,
    ROUND(
        CASE 
            WHEN SD_PT <> 0 THEN ((POINT * 1.0 - AVG_PT) * 10) / SD_PT + 50
            ELSE 50 
        END, 
        1
    ) AS DEV_VAL
FROM 
    TEST_RESULTS
    CROSS JOIN AvgPts 
    CROSS JOIN StdDev
WHERE 
    TEST_ID = '100' 
ORDER BY 
    DEV_VAL DESC, 
    USER ASC;