From 2009 onwards data contained are presented in accordance with the Polish Classification of Activities 2007 (PKD 2007). The changes introduced to the PKD 2007, in relation to the PKD 2004, result mainly the modifications concerning the scope, consisting in new groupings of types of activity (taking new onto consideration, division or aggregation of hitherto), and also in shifts of types of activity between particular classification levels. In consequence, the PKD 2007 makes distinction between 21 sections and 88 divisions, while the PKD 2004 - between 17 sections and 62 divisions. It should be noted too, that in certain cases, although the name of classification levels according to the PKD 2007 have remained unchanged, compared to the PKD 2004, data may not be comparable to the previously presented (according to the PKD 2004), given the abovementioned changes. Starting from 2009 the current data is published according to the PKD 2007. Data for previous periods are also converted according to this classification. Data within the scope of financial results of non-financial enterprises cover economic entities maintaining economic records and which are obliged to prepare quarterly reports on income, costs and the financial result - F-01/I-01 (with the exception of units in which the principal activity is classified as "Agriculture, forestry and fishing" and "Financial and insurance activities" according to NACE), which employ more than 49 persons. Since the first quarter 2012 data on bank credits and loans relate to liabilities to related parties and other entities together.