PGNiG Group announced production and sales results for the fourth quarter of 2017. For the quarter, the company increased external gas sales by 9.7% year-over-year to 8.025 billion cubic meters (bcm), while production increased 1.7% year-over-year to 1.18 bcm, compared with external gas sales of 7.34 bcm, while production of 1.16 bcm a year ago.