Also important for the interpretation of the wait events is the period over which the report was take. This is found at the end of report.txt
SQLDBA> Rem The times that bstat and estat were run. SQLDBA> select * from stats$dates; STATS_GATHER_TIMES -------------------- 07-nov-96 10:49:47 07-nov-96 11:16:16 2 rows selected. SQLDBA>