This publication provides information about changes in economy structure of Mazowieckie Voivodship in 2013 and 2014 using the data concerning the entities of the national economy registered in the REGON register.

The REGON register is created on the basis of information presented to it by entities. According to the rules and regulations, the entities are obliged to enter the register the moment they are set up or they undertake their activity. They are also obliged to register the changes of qualities included in register and deletion from the register.