How can I subtotal then average the subtotals
 

Hello all. I don't get to use excel alot so I am hoping someone can help me
out. Probably basic so please forgive me. I have a worksheet of orders for
a specific customer# (clmn A). It lists the order #(clmn B) part#(clmn C)
and part $$ (clmn D) and the order date (clmn E). I need to subtotal the
orders (order $) then get an average order value. The orders are a variety
of line items per order. I can subtotal but how do I get an average of all
the subtotals? Thanks for any tips/hints. running excel 2007, on XP SP3.