Hierarical Query Performance

Hi Folks,

I need a quick help from you. I have a hierarical query that is used in the front-end application.

WITH EMP ([EMP_ID],[NAME],  [MANAGER_NAME]  ,[MANAGER_ID], [CHGS]) AS 

(   SELECT [EMP_ID],[NAME],[MANAGER_NAME]  ,[MANAGER_ID], [CHGS]  FROM EMPLOYEE
 WHERE [MANAGER_ID]=101 or [EMP_ID]=101 and  BILLDATE  BETWEEN '10-APRIL-2013' and '10-MAY-2013'
  UNION all  
SELECT a.[EMP_ID], a.[NAME], a.[MANAGER_NAME]  ,a.[MANAGER_ID], a.[CHGS] FROm EMPLOYEE as a inner  JOIN EMP b ON a.[MANAGER_ID]=b.[EMP_ID]) 

SELECT round(sum(distinct([CHGS]))/100,0) as charges FROM EMP.

In Employee table there were 2000 records and it is taking 6 minutes.

Can you kindly suggest me how to improve the performance of this query. Appreciate your help.

Thanks,

Ven.