During the first quarter of 2016, the Company changed its operating segments to consist of (1) towers and (2) small cells. This change was as a result of growth in small cells from a combination of organic growth, capital expenditures, and acquisitions, as well as the continued progression of the integration of Sunesys, which led to changes in how the Company's chief operating decision maker ("CODM") reviews financial information. The Company's operating segment change aligns with how the CODM views and evaluates the Company's operations, including how the CODM allocates capital and assesses segment performance. The Company has recast its prior period presentation to conform to its current reporting presentation. The towers segment provides access, including space or capacity, to the Company's approximately 40,000 towers geographically dispersed throughout the United States. The tower segment also reflects certain network services relating to the Company's towers, consisting of site development services and installation services. The small cells segment provides access, including space or capacity, to the Company's small cell networks designed to facilitate wireless connectivity and supported by 16,500 miles of fiber. To a lesser extent, the small cells segment offers other fiber based solutions, including dark fiber (dedicated fiber strands lit by the customer) and lit fiber (bandwidth provided to the customer using the Company's own optronics). The measurement of profit or loss used by the CODM to evaluate the results of operations of its operating segments are (1) segment site rental gross margin, (2) segment network services and other gross margin, and (3) segment operating profit. The Company defines segment site rental gross margin as segment site rental revenues less segment site rental cost of operations, which excludes stock-based compensation expense and prepaid lease purchase price adjustments recorded in consolidated cost of operations. The Company defines segment network services and other gross marg