The following table has been used to initialize the calendar user types registry.
+--------------------+---------+-------------------------+ | Calendar User Type | Status | Reference | +--------------------+---------+-------------------------+ | INDIVIDUAL | Current | RFC 5545, Section 3.2.3 | | | | | | GROUP | Current | RFC 5545, Section 3.2.3 | | | | | | RESOURCE | Current | RFC 5545, Section 3.2.3 | | | | | | ROOM | Current | RFC 5545, Section 3.2.3 | | | | | | UNKNOWN | Current | RFC 5545, Section 3.2.3 | +--------------------+---------+-------------------------+