Newbie? or just lack of resources and training? PL/SQL Question

[Quoted] I've been placed in charge (I think because I was the only one not afraid of it) Intergraph Computer Aided Dispatch System Using Clix (read Intergraph's unix)
and these Oracle products:

ORAKRNL   SN01040 24-FEB-1993 06.00.33.05 ORACLE Base product (kernel) 
ORAKRNLRT SN01161 24-FEB-1993 06.00.33.05 ORACLE Base product (kernel) 
ORAPLUS   SN01045 24-FEB-1993 03.00.09.06 ORACLE SQL*Plus Utility      
ORAPLUSRT SN01162 24-FEB-1993 03.00.09.06 ORACLE SQL*Plus Utility - Run
ORATPO    SN01110 24-FEB-1993 06.00.33.05 ORACLE Transaction Processing

I have been trying to find the median of the difference between two timestamps.
(The bean counters are demanding a print out of what we could tell them
from
experience) I can not use the true average because there are enough aberations
to skew the results way to the high side. So the question is....

Is anyone familar with a method or command to derive the median of a set of numbers using PL/SQL? (I'm hoping for a command, because I've looked at a Statistics book
and I'm not sure I have the time to learn the formula)

For reference this is what I used to find the average:

SQL> select (avg(ds_ts - sdts))/60 from aeven   2 where curent='T' and PRIORITY < '4' and   3 cdts between '19960601000000' AND '19960630240000';

(AVG(DS_TS-SDTS))/60

              8.0189

All help or pointers greatfully accepted.

			Thom Woolverton ( dispatcher_at_tntonline.com )
			FIRE/EMS Emergency Dispatch
			Lee County, FL   

	http://www.tntonline.com/personal/911.htm