Monitor Table Usage

I used the below query to get the total physical reads/write by day:

select distinct
to_char(begin_interval_time,'mm/dd') c1,
sum(physical_reads_total) reads,
sum(physical_writes_total) writes
from
dba_hist_seg_stat s,
dba_hist_seg_stat_obj o
,dba_hist_snapshot sn
where
o.owner = 'SIEBEL'
and
s.obj# = o.obj#
and
sn.snap_id = s.snap_id
and
object_name = 'S_DOCK_TXN_LOG'
group by to_char(begin_interval_time,'mm/dd')
order by 1;