ExcelBanter - Calculating total amount in a Pivot Table

I'm importering af row of items (posts) from a bookkeeping system to a
Pivot Table

The posts are like this::

Order1, date, hours, amount
Order2, date, hours, amount

For each order there is 12 posts, one for each month in the year. Each
post has a number og hours and a total amount for the number og hours
(per month) times the hourly rate.

In the Pivot Table they look like this

Order Jan Feb Mar Apr Mai Jun Jul Aug Sep Oct Nov Dec Total hours
Order 1 2 1 4 2 1 4 5 6 3 1 4
2 35

I would like a sum for the total amounts to the right of total hours
(in the column right to Total hours)

However I cannot figure out how to do it.

The total amount is a sum of all the amounts for the months. However i
can get this by including the amounts in the table a placing the fielt
right under the hours så each order consist of 2 lines - one showing
the hours per month and one showing the amounts per month (and a
total). However i do not need the amounts per month but only as a sum
for all the months. And i like to have it show to the right of the
total hours (on one line).

I've tried looking at culculated fields but dont think that will do
it.

It is possible and how?