What is the total number of sites that American Tower plans to build in the next five years 
, and Africa, we continue to see solid demand for our critical infrastructure largely driven by deployments of legacy network technologies, particularly 4G.
Whether looking at Brazil, Mexico, India, or Nigeria, consumers are rapidly increasing their utilization of smartphones, thereby driving mobile data usage growth higher. In many of these regions, existing network infrastructure is insufficient to support this deluge of usage as cell site performance is challenged with increased levels of network load. In response to these trends, we are aggressively marketing our existing assets and continue to look for additional acquisition opportunities to bolster our footprint in these markets. But at the same time, we have significantly ramped up our new build program given the tremendous need for entirely new infrastructure.
In fact, if you take the nearly 5,900 sites we built last year and add our expected 7,000 sites at the midpoint of our outlook to be constructed this year, it would represent almost as many sites as the previous five years combined. And as we laid out a few quarters ago, we are targeting the construction of up to 40 to 50,000 new sites over the next five years. With day one NOI yields on these builds continuing to average above 10%, we are excited about deploying significant capital to these initiatives going forward as we capitalize on the advancement of network technology across the emerging world while helping to connect billions of people. In addition to the core secular growth trends driving our global tower business, we are seeing indications, particularly in more mature markets like the United States, of a broad evolution within the overall wireless ecosystem.
This evolution is closely intertwined with 5G and includes an increased prevalence of cloud-native network solutions, more emphasis on the various permutations of the network edge and an ever-increasing intersection of the wired and wireless portions of today's converged network architecture. As networks virtualize, O-RAN or Open RAN, it's expected to become a more important option to improve their economics. We are now starting to see this phenomenon with DISH in the United States, and in Germany, where one and one has spoken extensively about its intent to utilize this technology. By utilizing O-RAN, carriers have the potential to optimize network design and drive cost efficiencies, freeing up incremental capital to invest in densification and other network enhancements that help drive growth in site deployments and colocations.
Importantly, the role of the tower in this evolving network design is as critical as ever. While base station functionality will likely continue to evolve to be cloud native software agile, the radio equipment that is placed on the tower itself, which has always driven our revenue, will continue to reside on the tower. Importantly, we believe we can leverage our extensive global distributed real estate portfolio to not only drive continued strong growth in our core tower business but also to take advantage of other emerging opportunities as networks virtualize. This may include multi-access edge computing and potential other edge cloud permutations of neutral host infrastructure.
At the end of the day, modern software-driven networks are becoming smarter, faster, more capable, and more dynamic, and we are focused on ensuring that American Tower has a meaningful role to play in this context on the infrastructure and real estate side of the equation. One of the areas we focused on is the development of the network edge or, more accurately, the development of multiple layers of the network edge. With the need for lower latency expected to become more and more critical over time with applications like AR, VR, telemedicine, real-time analytics, autonomous driving, entertainment, streaming, you name it, and many others are beginning to emerge, we continue to believe that this could be a meaningful opportunity for American Tower. As we've done more work on the evolution of the edge, the concept of multiple edge layers has co
, and Africa, we continue to see solid demand for our critical infrastructure largely driven by deployments of legacy network technologies, particularly 4G.
Whether looking at Brazil, Mexico, India, or Nigeria, consumers are rapidly increasing their utilization of smartphones, thereby driving mobile data usage growth higher. In many of these regions, existing network infrastructure is insufficient to support this deluge of usage as cell site performance is challenged with increased levels of network load. In response to these trends, we are aggressively marketing our existing assets and continue to look for additional acquisition opportunities to bolster our footprint in these markets. But at the same time, we have significantly ramped up our new build program given the tremendous need for entirely new infrastructure.
In fact, if you take the nearly 5,900 sites we built last year and add our expected 7,000 sites at the midpoint of our outlook to be constructed this year, it would represent almost as many sites as the previous five years combined. And as we laid out a few quarters ago, we are targeting the construction of up to 40 to 50,000 new sites over the next five years. With day one NOI yields on these builds continuing to average above 10%, we are excited about deploying significant capital to these initiatives going forward as we capitalize on the advancement of network technology across the emerging world while helping to connect billions of people. In addition to the core secular growth trends driving our global tower business, we are seeing indications, particularly in more mature markets like the United States, of a broad evolution within the overall wireless ecosystem.
This evolution is closely intertwined with 5G and includes an increased prevalence of cloud-native network solutions, more emphasis on the various permutations of the network edge and an ever-increasing intersection of the wired and wireless portions of today's converged network architecture. As networks virtualize, O-RAN or Open RAN, it's expected to become a more important option to improve their economics. We are now starting to see this phenomenon with DISH in the United States, and in Germany, where one and one has spoken extensively about its intent to utilize this technology. By utilizing O-RAN, carriers have the potential to optimize network design and drive cost efficiencies, freeing up incremental capital to invest in densification and other network enhancements that help drive growth in site deployments and colocations.
 Importantly, the role of the tower in this evolving network design is as critical as ever. While base station functionality will likely continue to evolve to be cloud native software agile, the radio equipment that is placed on the tower itself, which has always driven our revenue, will continue to reside on the tower. Importantly, we believe we can leverage our extensive global distributed real estate portfolio to not only drive continued strong growth in our core tower business but also to take advantage of other emerging opportunities as networks virtualize. This may include multi-access edge computing and potential other edge cloud permutations of neutral host infrastructure.
At the end of the day, modern software-driven networks are becoming smarter, faster, more capable, and more dynamic, and we are focused on ensuring that American Tower has a meaningful role to play in this context on the infrastructure and real estate side of the equation. One of the areas we focused on is the development of the network edge or, more accurately, the development of multiple layers of the network edge. With the need for lower latency expected to become more and more critical over time with applications like AR, VR, telemedicine, real-time analytics, autonomous driving, entertainment, streaming, you name it, and many others are beginning to emerge, we continue to believe that this could be a meaningful opportunity for American Tower. As we've done more work on the evolution of the edge, the concept of multiple edge layers has co