Poland’s dominant gas firm PGNiG booked impairments which diminished its operating profit by 624 million zlotys ($156 million) in the second quarter of 2016, the company said on Thursday.

“The biggest impact on the impairments came from long-term macroeconomic assumptions, especially forecasts regarding prices of oil and gas,” it said in a statement.

The impairments concern mainly the group’s exploring and producing segments.