I don't have much information about the columns, However we have an information about usage summary how it's manipulated and information about PRPC tables PR_USAGE_SUMMARY, PR_DAILY_USAGE, PR_HOURLY_USAGE.
Pega provides a stored procedure(SPPR_AGGREGATE_USAGE) in the PegaRULES schema which summarizes hourly data in pr_hourly_usage and daily usage in pr_daily_usage tables.
Stores daily usage summaries (Log-License-Usage-Daily class) on requestor and background process use of rules for license compliance.
Stores hourly data summaries on requestor and background process use of rules for license compliance. A rough estimate of number of records is Number of Users * 24 hours * 8 days, the retention period. This table should not be partitioned
Stores summaries of a customer’s license compliance data; depending on the license configuration, a record can summarize data for a month, a quarter, or a year. Assume the table stores 7 years of quarterly summaries