Correct number with dynamic sampling level 8 but wrong with 9

Hi All,

My DB is 11.1.

The SQL looks like:

SELECT <font color="#006400">/*+ parallel(SHPMT,4) dynamic_sampling(SHPMT 8)*/</font>
       *
  FROM OMTH_SFCT SHPMT,
       O_1_SFCT    PRMTN_PROD,
       O_DIM             PROD
 WHERE PRMTN_PROD.BID = PROD.BID
   AND PRMTN_PROD.BID = SHPMT.BID
   AND PRMTN_PROD.PID = SHPMT.PID
   AND PRMTN_PROD.PID = PROD.PID
   AND PRMTN_PROD.PRID = SHPMT.PRID
   AND SHPMT.DATE_ID >= SYS_CONTEXT(<font color="#000080">'APP_CTX'</font>,<font color="#000080">'MIN_DATE_SKID'</font>)
   -- sys_context returns 10000

The plan looks like

--------------------------------------------------------------------------------------
| Id  | Operation                                | Name                     | Rows  |
--------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT                         |