XSL

hi

I am developing an XSL file to view the tasks and some information about
it in a web page.

The reason is because my boss has MS winkk and i can't show him the
status of my tasks.

I've a problem to calculate the "task duration". If anybody can send me
the function or the math algorythm to do that ..  i'd be very grateful
(I can't find it in the mrproject source)

thanks .. 

Martin Arrieta