National Australia Bank business deposits have decreased over the last two months, according to APRA's monthly banking statistics.The major player in the market remains National with a book of $63 billion, which has decreased by $830 million since June, with an increase during calendar year 2008 of less than two per cent.ANZ currently has $51 billion in business deposits, with growth difficult to determine due to the reclassification of loans for the period. Commonwealth calculations are equally difficult due to an accounting change applied mid-year, with the book $46 billion ending August.Westpac and St George both increased three per cent for the month to $43 billion and $20 billion respectively, with the potential combined total post merger able to rival National. The BankWest business deposit book has fallen five per cent this year to $16.6 billion.On the asset side National is the dominant business lender with $82 billion outstanding as at August, an increase of six per cent for 2008.ANZ reported $71 billion in business loans, up ten per cent this year, with Commonwealth and Westpac both having $61 billion, with percentage changes again difficult to calculate due to recent reclassification of loans.