select
	USER, PT,
	case
		when SQRT(AVG(AVG_POINT_POW) OVER()) = 0 then 50.0
		else ROUND(AVG_POINT * 10.0 / SQRT(AVG(AVG_POINT_POW) OVER()) + 50.0, 1)
	end as DEV_VAL
from
	(select
		USER_ID as USER,
		POINT as PT,
		POINT - AVG(POINT) OVER() AVG_POINT,
		POW(POINT - AVG(POINT) OVER(), 2) AVG_POINT_POW
	from
		TEST_RESULTS
	where
		TEST_ID = '100'
	)
order by
	DEV_VAL desc, USER