JobParameter severity in CPS monitor tree

Hello All ,

Our redwood version is M33.120 . when i went trough monitoring tree the size of JobParameter severity is 50 in Quality and 75 in production for our CPS servers.

we maintain a data of last 1 year . Actually there is no Keep clause value mentioned for each job under job definitions. In order to remove the history of the jobs which are more than 1 year are removed using the below standard jobs which run periodically .

System_RemoveOldJobs

System_RemoveOperatorMessages

System_ArchiveEvents

And additionally by default the system jobs regularly.

I want to know how to decrease the severity of JobParameter where there are high no of rows and delta values. and whats are the steps to be taken care of to decrease the severity.