WRH Stats table size does not get purged

 ====================================================== Oracle is currently working on an SR on this topic, while we are diagnosing the problem
we are opening up this question to our user community so they can add perspective to the
solution based on their real world experience.
======================================================

WRH$_ACTIVE_SESSION_HISTORY and WRH$_LATCH_CHILDREN tables have grown to immense sizes and contain old data going back 2
years despite retention being set to 30 days.

SEGMENT_NAME                                            MBYTES
-------------------------------------------------- -----------
WRH$_ACTIVE_SESSION_HISTORY_PK                        8,942.19
WRH$_LATCH_MISSES_SUMMARY_PK                          1,346.00
WRH$_LATCH_CHILDREN_PK                               28,035.00
WRH$_ACTIVE_SESSION_HISTORY                          45,981.81
WRH$_LATCH_MISSES_SUMMARY                             1,159.00
WRH$_SQLSTAT                                          1,286.00
WRH$_LATCH_CHILDREN                                  44,070.00


Thanks