Thank you, Andi. Good afternoon, ladies and gentlemen. Welcome to our conference call for the first quarter 2018 result. We really appreciate your participation in this conference.
Ladies and gentlemen, despite the challenging condition as the impact of intense competition in cellular business, combined with the SIM card registration implementation, our revenues still grew by 4.3% year-on-year to IDR 32.3 trillion, supported by encouraging progress in fixed line businesses. Data, Internet and IT Service significantly grew by 23.3% year-on-year as a result of strong growth in mobile broadband, ICT solution in Enterprise and IndiHome. Our EBITDA declined 4.1% to IDR 16.1 trillion, and net income dropped by 14.3% to IDR 5.7 trillion as we continue our effort to deploy broadband infrastructure, both in mobile and fixed, resulted in high operating and maintenance and also depreciation expenses. While on a quarterly basis, revenue, EBITDA and net income grew by 3.5%, 10.7% and 55.8%, respectively.
Ladies and gentlemen, our mobile subsidiary, Telkomsel, recorded revenue of IDR 21.9 trillion, declined by 1.9% as an impact of declining legacy business and very intense competition in pricing, particularly during SIM card registration period; while EBITDA declined by 9.2% to IDR 12.0 trillion; and net income dropped by 16.7% to IDR 6.4 trillion as Telkomsel continued to strengthen its network, resulting in higher operating and maintenance and depreciation costs. Nevertheless, Telkomsel remain focused on growing its Digital Business to take advantage from the increasing of smartphone penetration and respond to the declining legacy businesses.
The Digital Business recorded a significant revenue growth of 24.8% year-on-year, accounted for 48% of total revenue, increased significantly from 37.7% a year ago. The growth in Digital Business was a result of our network superiority as we deploy more than 6,900 new BTSs during the first quarter of 2018. All were 4G BTSs. By the end of March, our BTS, on average, more than 167,000 units, increased 23.2% year-on-year, around 70% of which were 3G and 4G BTS.
Our data traffic subtly increased by 145.8% year-on-year to 8,000 -- 99,600 terabyte, mainly fueled by high growth in 3G- and 4G-capable device that reached 115.3 million, grew 20 -- 35.2% year-on-year. It represented 59% of our customer base.
Telkomsel also continue its effort to develop digital ecosystem in digital service, including digital lifestyle, mobile financial service and digital advertising.
Ladies and gentlemen, let me now share about the progress in fixed line businesses. We intensified to roll out our fixed broadband service, and we reached 3.5 million total IndiHome subscribers by the end of March 2018, increased by 97% year-on-year. Sales and technician productivity significantly improved partly as a result of enhanced IT system that helped us to manage our resources more effectively. In the first quarter, net addition line reached 500...