Mobile operator Polkomtel has announced that its first half net profit fell by 3.8% year on year to PLN506.8 million (USD167.8 million), due to higher cost of sales and falling tarriffs. At the end of June 2006 Polkomtel had 10.4 million users up from 7.9 million a year earlier; the larger customer base helped it increase revenue to PLN3.54 billion, from PLN3.06 billion, but also contributed to a 20% rise in costs of sales to PLN2.87 billion, from PLN2.40 billion. APRU fell by 13.6% year on year to PLN55.2.