performance issue (repost)

[Nipon]

Hi,
A table which I schedule DB maintenance to REORGANIZE DATA AND INDEX
PAGES with THE ORIGINAL OF FREE SPACE every night, but during the day
, I check with SHOWCONTIG the result is as following:

DBCC SHOWCONTIG scanning 'INV_HEAD_TRANSACTION' table...
Table: 'INV_HEAD_TRANSACTION' (1827537594); index ID: 1, database ID:
10
TABLE level scan performed.
- Pages Scanned................................: 259
- Extents Scanned..............................: 40
- Extent Switches..............................: 98
- Avg. Pages per Extent........................: 6.5
- Scan Density [Best Count:Actual Count].......: 33.33% [33:99]
- Logical Scan Fragmentation ..................: 31.27%
- Extent Scan Fragmentation ...................: 32.50%
- Avg. Bytes Free per Page.....................: 1177.9
- Avg. Page Density (full).....................: 85.45%
DBCC execution completed. If DBCC printed error messages, contact your
system administrator.

As you can see the Scan Density is lower from about 80% up (result
from scheduled DB maintenance) to 33.33% in about 3 hours (8.00 -
10.00).

Is this an usual result (the process of this table is mostly
INSERT/UPDATE) because users complain about slow performance?

Can I do anything else to the DATABASE during the working day?

Any suggestion or advise would be very appreicated.

Thank you in advance
Nipon Wongtrakul