Registration updated every round
After the startup (census) core baseline round where all households and members of the DSS are registered, all subsequent rounds are concerned with updating events in this population.  In the HRS system, the Household Registration or Record Book (HRB) is the key document.  Depending on what events are occurring during the update period, additional forms are used to capture the details on these core events.  Some events need to be captured on a continuous basis such as pregnancies, births and deaths and these core events need to be recorded during every update round of the DSS. These are outlined in sub-sections of this section.
Other events such as education status may only change once per year and only need to have registration updated annually or less frequently.