Logging requirement for 5 years

What are the requirements for the 5 years of logging in terms of data and in terms of logging interval? We will already be logging whole building water usage in Portfolio Manager on a monthly basis for 5 years per the "Building-level water metering" prerequisite. Does this credit require that we log weekly for 5 years instead of monthly? Also, must we log the sub-metered data separately in Portfolio Manager or is whole building data sufficient? We'll get the whole building data from the monthly water bills. Our sub-meters must be read manually. It would be time consuming to walk around the building each month (or week) for 5 years, record that data, post it to Portfolio Manager, and deduct those quantities from the whole building meters.