Another way to know how much inserts ,delete ,update has taken in a table is by a feature called monitoring.
just give
alter table emp monitoring;
analyze table emp compute statistics;
insert 5 rows in emp;
delete 10 rows in emp;
update 5 rows in emp;
cool down for three to four hours or give a shutdown immediate then
SELECT * FROM SYS.DBA_TAB_MODIFICATIONS;
but these this has some limitations.Pls check whether it helps or not
