with
	a1 as (
		select
			point
			,avg(point) over () as average
			,point - avg(point) over () as sabun
			,(point - avg(point) over ()) * (point - avg(point) over ()) as nijou
			,user_id
		from
			test_results
		where
			test_id = '100'
	)
	,a2 as (
		select
			avg(nijou) as nijou_ave
			,sqrt(avg(nijou)) as stdev
		from
			a1
	)

select
	user_id as USER
	,point as PT
	,round(case
		when stdev = 0 then 50
		else (point - avg(point) over()) * 10 / stdev + 50
		end, 1) as DEV_VAL
from
	a1
	cross join a2
order by
	3 desc, 1