Crown Castle International Corp. raised its 2017 earnings outlook, as the company recorded a 9% year-over-year gain in adjusted funds from operations for the fourth quarter of 2016.

Fourth-quarter 2016 AFFO rose 9% to $406.4 million from $372.2 million in the fourth quarter of 2015. Meanwhile, FFO came to $386.9 million, down from $410.3 million in the year-ago quarter. Site rental revenues climbed 4% over the previous year, while site rental gross margin was 3% higher than in the year-ago quarter.

For the full year 2016, AFFO hit about $1.61 billion, up from roughly $1.44 billion in 2015. FFO for the year came to about $1.43 billion, down from $1.53 billion a year ago.

"During 2016, we increased our dividends per share by 8%, exceeding our long-term goal of 6% to 7% annual growth. With our recent acquisition of FiberNet, which closed in January, we now own approximately 40,000 towers and over 26,500 route miles of fiber in key metro markets throughout the US," CEO Jay Brown said in a release.

Looking ahead, the company said it expects AFFO for the 2017 first quarter to range from $440 million to $445 million, and to hit a range of about $1.80 billion to $1.83 billion for the full year. Previously, Crown Castle predicted AFFO to hit a range of roughly $1.74 billion to $1.77 billion, and about $1.57 billion to $1.60 billion for FFO. Meanwhile, FFO for the first quarter is projected in the range of $395 million to $400 million, and in the range of about $1.62 billion to $1.65 billion for the full year.