There is the issue that the two methodologies give different results, also ...
Code:
alter session set nls_date_format = 'DD-Mon-YYYY Day';

select
   min_dte,
   max_dte,
   working_days(min_dte,max_dte) wd,
   business_days_between(min_dte,max_dte) bdb
from
   table_name
where
   rownum <100 and
   working_days(min_dte,max_dte) != business_days_between(min_dte,max_dte)
/

MIN_DTE               MAX_DTE                       WD        BDB
--------------------- --------------------- ---------- ----------
14-Aug-2002 Wednesday 16-Aug-2002 Friday             2          3
11-Aug-2002 Sunday    13-Aug-2002 Tuesday            3          2
08-Aug-2002 Thursday  10-Aug-2002 Saturday           1          2
04-Aug-2002 Sunday    06-Aug-2002 Tuesday            3          2
03-Aug-2002 Saturday  05-Aug-2002 Monday             2          1
01-Aug-2002 Thursday  03-Aug-2002 Saturday           1          2
31-Jul-2002 Wednesday 02-Aug-2002 Friday             2          3
27-Jul-2002 Saturday  29-Jul-2002 Monday             2          1
24-Jul-2002 Wednesday 26-Jul-2002 Friday             2          3
21-Jul-2002 Sunday    23-Jul-2002 Tuesday            3          2
18-Jul-2002 Thursday  20-Jul-2002 Saturday           1          2

MIN_DTE               MAX_DTE                       WD        BDB
--------------------- --------------------- ---------- ----------
13-Jul-2002 Saturday  15-Jul-2002 Monday             2          1
11-Jul-2002 Thursday  13-Jul-2002 Saturday           1          2
10-Jul-2002 Wednesday 12-Jul-2002 Friday             2          3
07-Jul-2002 Sunday    09-Jul-2002 Tuesday            3          2
03-Jul-2002 Wednesday 05-Jul-2002 Friday             2          3
30-Jun-2002 Sunday    02-Jul-2002 Tuesday            3          2
29-Jun-2002 Saturday  01-Jul-2002 Monday             2          1
27-Jun-2002 Thursday  29-Jun-2002 Saturday           1          2
22-Jun-2002 Saturday  24-Jun-2002 Monday             2          1
19-Jun-2002 Wednesday 21-Jun-2002 Friday             2          3
16-Jun-2002 Sunday    18-Jun-2002 Tuesday            3          2

MIN_DTE               MAX_DTE                       WD        BDB
--------------------- --------------------- ---------- ----------
13-Jun-2002 Thursday  15-Jun-2002 Saturday           1          2
09-Jun-2002 Sunday    11-Jun-2002 Tuesday            3          2
08-Jun-2002 Saturday  10-Jun-2002 Monday             2          1
06-Jun-2002 Thursday  08-Jun-2002 Saturday           1          2
05-Jun-2002 Wednesday 07-Jun-2002 Friday             2          3
01-Jun-2002 Saturday  03-Jun-2002 Monday             2          1
29-May-2002 Wednesday 31-May-2002 Friday             2          3
26-May-2002 Sunday    28-May-2002 Tuesday            3          2
23-May-2002 Thursday  25-May-2002 Saturday           1          2
18-May-2002 Saturday  20-May-2002 Monday             2          1
16-May-2002 Thursday  18-May-2002 Saturday           1          2
...
It looks like working_days has a bug.

I note that business_days_between is also inclusive of both min_dte and max_dte, and working_days is not, but that's a diff issue.