Indonesia’s largest telecoms group PT Telekomunikasi Indonesia (Telkom Indonesia) says its net income for 2011 fell 5% year-on-year to IDR10.97 trillion (USD1.20 billion) as a result of rising operating costs. The telco recorded revenue of IDR71.25 trillion last year, up from IDR68.63 trillion in FY2010, driven by strong gains at its data and internet divisions which offset falling sales and margins at its traditional (core) voice business. Telkom Indonesia said turnover derived from data and internet services expanded 20.8% year-on-year to IDR23.90 trillion – equivalent to 34% of the consolidated total. The gains helped to mitigate declining ARPU from Telkom’s Telkomsel mobile arm, which nonetheless added a net 13 million subscribers last year for a year end total of 107 million. Telkomsel reported that intense competition amongst the country’s dozen mobile players resulted in a 7.0% decline in average revenue per user (ARPU) last year, compared to FY2010. Operating expenses climbed by 8.0% y-o-y in FY2011, as Telkom worked to meet increased costs relating to an early-retirement programme. Personnel costs jumped 16.7% to IDR8.56 trillion in FY2011.