Payment on Account

System

Just getting started as self emplyed doing first set of books. Accounts ok but is this how POA works<BR><BR>Assume computation<BR><BR>Year 03/04 Profits and NIC payable 2000<BR><BR>payment on account on profit made<BR>in year 02/03<BR> Jan 04 1500<BR> July 04 1200 2700<BR>balance for Jan 05 (700)<BR><BR>IR rebates Mar 05 500<BR><BR>Year 04/05 Profits and NIC 1500<BR><BR>Payment on account<BR><BR> Jan 05 2000/2 + 500+ (700) = 800<BR> July 05 2000/2 = 1000<BR><BR>Is this the corect calculation or have i got the whole thing wrong. Excuse the greeness.<BR><BR>Thanks in advance