how to calculate percentage in sql

[yvr238]

Here is the code ,instead of sum(t.regularhours) i want percentage of t.regularhours please help me out i kept this formula for total hours --
t.regularhours/(select sum(regularhours) from time t)*100 but i got the error as this t.regularhours is not contained in either aggregate or group by function.but when i keep group by w.name,res.employeetype,t.regularhours
i get all the workgroupnames without getting grouped

SELECT
ISNULL(w.Name, 'N/A') AS WorkGroupName,
'Project' as TimeType,

case when res.employeetype ='NT' then 'NTNI'
when res.employeetype= 'EM' then 'Employee'
when res.employeetype= 'CO' then 'Contractor'
when res.employeetype= 'MC' then 'Management Consultant'
when res.employeetype= 'OS' then 'Offshore'
end Employeetype,
Sum(t.RegularHours) AS RegularHours
FROM
Time t (NOLOCK) LEFT OUTER JOIN
Workgroupmember wgm (NOLOCK) ON t.ResourceId = wgm.ResourceId and t.WorkgroupId=wgm.WorkgroupId and t.GlobalWorkgroupId=wgm.GlobalWorkgroupId LEFT OUTER JOIN
Workgroup w (NOLOCK) ON w.WorkgroupId = wgm.WorkgroupId and w.deleted = 0 LEFT OUTER JOIN
GlobalWorkgroup gwg (NOLOCK) ON wgm.GlobalWorkgroupId = gwg.GlobalWorkgroupId LEFT OUTER JOIN
Resources res (NOLOCK) ON wgm.ResourceId = res.ResourceId
where timedate >'12/10/2005' and approvalstatus='A' and w.obs like '00001.00004.00001%'
group by w.name,res.employeetype

[jedicoder]

Try this:
1. Include another column in your SQL which is t.RegularHours.
2. ...then wrap that sql in a SQL statement that actually calculates the percentage. (make it a subquery).