Data refer only to units that have submitted a report. In the case of research in this field an imputation procedure for missing data is not applied. The 2010 population balance data have been prepared according to the administrative division of the country as of 1 January 2011, however due to the specificity of the Local Data Bank they have been recalculated according to the administrative division of the country as of 1 January 2010 (excluding changes that do not affect the indices or the names of territorial division units). This has resulted in a difference to the data published in Statistics Poland reports. For comparison, the information on five gminas (rural in 2010 and urban-rural in 2011) according to the administrative division of the country as of 1 January 2011 for 2010 is available in this report - download file. For the years 2000–2007 information on water supplied do not include values for subregions.