Dear,
Go to SE16 and give the VBFA table ,execute Field VBTYP_N with " U " then you can see Proforma Invoices and also with Sales Documents but you can not see Commercial Invoices or else go by thru Document flow Tables or else go by creation of SQVI Query to get the exact report .
Note : I think ,at time ,we may not get both numbers by Single Table .Best one is try by Query level .
Thanks,
Naren