How do increase this procedure performance?

Hi
Please suggest me how do increase this stored procedure performance.

CREATE PROCEDURE [dbo].[HV2_rptAttributeTrendingDetailByMonth]
@ClientID int,
@CampaignList varchar(1000),
@LocationList varchar(1000),
@VendorList varchar(1000),
@AgentList varchar(1000),
@ShowByDate int,
@YearMonth char(6)
AS
/****************************************************************************************************************************
* Date: 11 th Feb, 2008
* Author: Biswajit Das, HQ
* Purpose: Monthly Attribute Trending Detail
* Client: Cingular
* Notes:

Kodiak--
exec HV2_rptAttributeTrendingDetailByMonth_J1382 2,'2','2','2','855',1,'200709'
**POPCORN
exec HV2_rptAttributeTrendingDetailByMonth 2,'0','0','0','2',1,'200802'
Duke

*****************************************************************************************************************************/
BEGIN
Declare @Year char(4), @Month integer
Declare @EvalStartDate datetime, @EvalEndDate datetime
Declare @CallStartDate datetime, @CallEndDate datetime
Declare @YearEnd char(10), @OverAllScore numeric(15,2), @Goal float

--set last day of year for filter on LeaveDate
set @YearEnd = '12/31/' + cast(year(getdate()) as char(4))
set @Year = left(@YearMonth,4)
set @Month = cast(right(@YearMonth,2) as integer)
set @CallStartDate = case when @ShowByDate = 1 then DateAdd(m,-5,Convert(Datetime,cast(@Month as varchar(2))+ '/1/' + @Year)) else '01/01/1900' end
set @CallEndDate = case when @ShowByDate = 1 then dateadd(d,-1,(dateadd(m,6,@CallStartDate))) else '12/31/2050' end
set @EvalStartDate = case when @ShowByDate = 2 then DateAdd(m,-5,Convert(Datetime,cast(@Month as varchar(2))+ '/1/' + @Year)) else '01/01/1900' end
set @EvalEndDate = case when @ShowByDate = 2 then dateadd(d,-1,(dateadd(m,6,@EvalStartDate))) else '12/31/2050' end


CREATE TABLE #users
(userid int)

INSERT INTO #users
select UserID from dbo.getDirectReportsCVL(@ClientID,@AgentList,@CampaignList,@LocationList,@VendorList,1)

DECLARE @MonthTable Table
(
CalendarYear int
,MonthNumber int
,MonthBeginDate datetime
,MonthEndDate datetime
,PRIMARY KEY (CalendarYear, MonthNumber)
)


select @Goal = max(UpperLimit)
from dbo.Threshold
where ClientID = @ClientID
and Type = 'Goal'

if (@month<6)
begin
Declare @Yearprevious char(6)
set @Yearprevious =@Year-1
insert @MonthTable
select CalendarYear, MonthNumber, min(FullDateID), max(FullDateID)
from dbo.DimDate
where CalendarYear =@Yearprevious and MonthNumber between left(convert(CHAR(11),@CallStartDate,101),2) and 12
group by CalendarYear, MonthNumber

insert @MonthTable
select CalendarYear, MonthNumber, min(FullDateID), max(FullDateID)
from dbo.DimDate
where CalendarYear =@Year and MonthNumber between @Month-5 and @Month
group by CalendarYear, MonthNumber
End

else
begin

insert @MonthTable
select CalendarYear, MonthNumber, min(FullDateID), max(FullDateID)
from dbo.DimDate
where CalendarYear =@Year and MonthNumber between @Month-5 and @month
group by CalendarYear, MonthNumber

end

/****Select CallStarDate & Endates as per Month dates as discussed **** */
Set @CallStartDate = (Select min(MonthBeginDate) from @MonthTable)
Set @CallEndDate = (Select max(MonthEndDate) from @MonthTable)


--select * from @MonthTable


select
m.CalendarYear
,m.MonthNumber
,m.MonthBeginDate
,m.MonthEndDate
,q.QuestionID
,f.CallEvalID
,f.CallID
,q.GroupSortOrder
,q.QuestionGroupName
,q.QuestionSortOrder
,q.QuestionName
,form.SortOrder as FormSortOrder
-- ,form.FormName
-- ,f.ActualPoints
-- ,q.PossiblePoints
,case when f.ActualPoints < 0 then 0 else q.PossiblePoints end as PossiblePoints
,case when f.ActualPoints < 0 then 0 else f.ActualPoints end as ActualPoints
,f.AgentID
,ans.AnswerName

,@Goal as Goal
,ff.weightedscore as InitialAP
,ff.weight as InitialPP

from


factlineitem f
join dbo.DimAnswer ans on (f.AnswerID=ans.AnswerID)
join dbo.DimDate d on d.FullDateID = case when @ShowByDate = 1 then f.CallDate else f.EvalDate end
join dbo.DimQuestion q on f.QuestionID = q.QuestionID
join @MonthTable m on d.CalendarYear = m.CalendarYear and d.MonthNumber = m.MonthNumber
join dbo.DimForm form on form.formid = q.formid
join dbo.FactCallEvaluation fc on f.CallEvalID=fc.CallEvalID
join dbo.FactFormEvaluation ff on f.CallID=ff.CallID and ff.FormID=f.FormID

where
f.ClientID = @ClientID
and (f.CampaignId in (select Param from dbo.getCSVtoTable(@CampaignList,',')) or @CampaignList = '0')
and (f.LocationId in (select Param from dbo.getCSVtoTable(@LocationList,',')) or @LocationList = '0')
and (f.VendorId in (select Param from dbo.getCSVtoTable(@VendorList,',')) or @VendorList = '0')
and (f.CallDate >= @CallStartDate and f.CallDate <= @CallEndDate)
and (f.EvalDate >= @EvalStartDate and f.EvalDate <= @EvalEndDate)
--and ans.AnswerName not in ('N/A' ,'NA')
and q.PossiblePoints > 0
and q.QuestionGroupName <> ' '
and (q.AutofailFlag is null OR q.AutofailFlag = 'N')
and q.deductFlag is Null
and ans.Elementname<>'COMMENT'
and ans.Elementname<>'Comments'
and fc.evalcount=1
and q.ScoreableFlag = 'Y'
and (f.AgentID in (select distinct UserID from #users))
order by
form.FormID,
form.SortOrder,
q.GroupSortOrder,
q.QuestionSortOrder




END