Books of account must run natural persons, civil law partnerships of natural persons, general partnerships of natural persons, professional partnerships and social cooperatives, of which net sales of goods, products and financial transactions behind 2013 amounted to the financial year 5 059 560 PLN (1 200 000 × euro 4.2163 PLN/EUR according to the trip of the table with No. 189 / A/NBP/ 2013 from 30 September 2013).