The increase in sales volume was generated from the sale of electricity to business customers - an increase of 1 250 GWh, i.e. by over 10%. The volume of electricity sold in the household segment remained at a similar level as compared to the previous year (99.3% dynamics). On the other hand, the volume of gas sales decreased. In 2017, total sales revenue increased by nearly PLN 50 million. It resulted from a 3% increase in sales revenues to business customers, i.e. PLN 93 million. Revenues from sales to household customers decreased as a result of the adjustment of regulated tariff prices.