To update the degree of processing for an activity, you have to confirm the activity. Confirming an activity is an action that records the actual data for an activity, such as actual start and finish dates, actual work and costs, and actual degree of processing. The degree of processing is a percentage value that indicates how much of an activity has been completed. Reference: https://help.sap.com/doc/0f069b2e08b748f1b480d4c8b46c3c49/100/en-US/6a7a9f0a6e421014e10000000a174cb4.html