Crystal reports Displaying column data in one row

I want to display few rows of data in a one column and i am using the below 3 formula method:

Group header

WhilePrintingRecords; Shared StringVar hazards := ""; If Not InRepeatedGroupHeader Then hazards := ""; 

Detail section

WhilePrintingRecords; if ( {CARRIERLOADBYJOB.REDUNDANT_STOCK_ID} in StringVar hazards ) then StringVar hazards := hazards else StringVar hazards := hazards + {CARRIERLOADBYJOB.REDUNDANT_STOCK_ID} + ', ' ; 

Footer section

WhilePrintingRecords; if length(trimright(StringVar hazards)) > 1 then StringVar hazards else StringVar hazards := left(hazards, (length(trimright(hazards)) - 1)); 

expected result is 80045,85263

but i am getting a result as 8920,5269,80045,85263

few additional records from the different is getting accumulated for the result. any help to omit the additional records