What is the company's industry-leading tower revenue growth rate for the first quarter of 2022 
 in the U.S. first.
And we've certainly seen that trend in -- as 5G has started to be deployed. I think that's one of the reasons why we have industry-leading tower revenue growth at 6%. I also think it's indicative of what we're going to see on the small cell side. The vast majority of the investment that we've made in fiber and small cells has been in those top 30 markets in the U.S.
It's the locations where we believe the vast majority of the capital will be going for the densification efforts, at least in the near to medium term. And over the long term, we think those assets, much like towers have in those urban areas, the investment will skew toward that urban activity and future densification. So some of the best assets are in those dense urban areas. We think we'll see a similar thing with fiber and small cells that we've seen historically with towers and are experiencing as we move into 5G already with the tower footprint.
On your second question, we certainly believe that there's an opportunity around edge data centers and have positioned ourselves several years ago with our investment in Vapor to take advantage of that opportunity. I would put that in the category of -- that's an upside case for us. If data traffic gets to the point where edge data centers become a meaningful component of the overall wireless network, an upside case in our investment in small cells and fiber. We did not underwrite that in our base case nor are we underwriting it day to day as we invest in fiber and small cells.
But if you're a believer that ultimately, there's going to be so much data traffic in the network that these metro data centers or edge data centers are going to be necessary for wireless, we're going to be in the upside outcomes for our small cells and fiber. And so we're certainly positioned well for that opportunity. And I would say, today, it seems more probable that that's a likely outcome than what we would have said several years ago, but it's not in our base case underwrite as we think about what the growth and returns will be on the assets. But there are certainly some signs as referenced earlier in some of the questions -- in the question around fixed wireless that would suggest maybe that opportunity is growing and becoming more likely.
And I would start first with the benefit we're going to get out of fiber and small cells as a result of that. And I think we're really well-positioned vis-a-vis the fiber and our investment in Vapor to benefit if we get all the way to the upside cases where these edge data centers are necessary and critical components for the wireless networks.
Michael Rollins -- Citi -- Analyst
Thanks.
Operator
We'll hear next from Phil Cusick with J.P. Morgan.
Phil Cusick -- J.P. Morgan -- Analyst
Hey, guys. Just a summary, and I apologize if you pressed a few of these already. But as you think about the activity through this year, do you expect activity to be ramping through this year? It sounds like it. And then do you think that can be maintained next year? Or are there other carriers that are sort of going to be coming down, do you expect?
Jay Brown -- Chief Executive Officer
Phil, as we think about any given year, and I think we've talked about some on the call as we've tried to point to some of the onetime items in the first quarter. When we think about the guidance and the outlook on an annual year-over-year basis because we think it's the best way to look at the business, as we get further into the back half of the year, maybe we can be a little bit more descriptive about the ramp in activity and what we're seeing is falling into the first half versus the second half of the year. But in general, this is shaping up to be a pretty normal year in terms of the way the activity is loaded into a calendar year. I don't want to really get into giving guidance for 2023.
We typically or historically have done that in October, and we would expect to do that again this year. So we're two calls away from giving you an outlook for 2023.
Phil Cusick -- J.P. Morgan -- Analyst
I guess. Thank you.
Oper
 in the U.S. first.
And we've certainly seen that trend in -- as 5G has started to be deployed. I think that's one of the reasons why we have industry-leading tower revenue growth at 6%. I also think it's indicative of what we're going to see on the small cell side. The vast majority of the investment that we've made in fiber and small cells has been in those top 30 markets in the U.S.
It's the locations where we believe the vast majority of the capital will be going for the densification efforts, at least in the near to medium term. And over the long term, we think those assets, much like towers have in those urban areas, the investment will skew toward that urban activity and future densification. So some of the best assets are in those dense urban areas. We think we'll see a similar thing with fiber and small cells that we've seen historically with towers and are experiencing as we move into 5G already with the tower footprint.
On your second question, we certainly believe that there's an opportunity around edge data centers and have positioned ourselves several years ago with our investment in Vapor to take advantage of that opportunity. I would put that in the category of -- that's an upside case for us. If data traffic gets to the point where edge data centers become a meaningful component of the overall wireless network, an upside case in our investment in small cells and fiber. We did not underwrite that in our base case nor are we underwriting it day to day as we invest in fiber and small cells.
But if you're a believer that ultimately, there's going to be so much data traffic in the network that these metro data centers or edge data centers are going to be necessary for wireless, we're going to be in the upside outcomes for our small cells and fiber. And so we're certainly positioned well for that opportunity. And I would say, today, it seems more probable that that's a likely outcome than what we would have said several years ago, but it's not in our base case underwrite as we think about what the growth and returns will be on the assets. But there are certainly some signs as referenced earlier in some of the questions -- in the question around fixed wireless that would suggest maybe that opportunity is growing and becoming more likely.
 And I would start first with the benefit we're going to get out of fiber and small cells as a result of that. And I think we're really well-positioned vis-a-vis the fiber and our investment in Vapor to benefit if we get all the way to the upside cases where these edge data centers are necessary and critical components for the wireless networks.
Michael Rollins -- Citi -- Analyst
Thanks.
Operator
We'll hear next from Phil Cusick with J.P. Morgan.
Phil Cusick -- J.P. Morgan -- Analyst
Hey, guys. Just a summary, and I apologize if you pressed a few of these already. But as you think about the activity through this year, do you expect activity to be ramping through this year? It sounds like it. And then do you think that can be maintained next year? Or are there other carriers that are sort of going to be coming down, do you expect?
Jay Brown -- Chief Executive Officer
Phil, as we think about any given year, and I think we've talked about some on the call as we've tried to point to some of the onetime items in the first quarter. When we think about the guidance and the outlook on an annual year-over-year basis because we think it's the best way to look at the business, as we get further into the back half of the year, maybe we can be a little bit more descriptive about the ramp in activity and what we're seeing is falling into the first half versus the second half of the year. But in general, this is shaping up to be a pretty normal year in terms of the way the activity is loaded into a calendar year. I don't want to really get into giving guidance for 2023.
We typically or historically have done that in October, and we would expect to do that again this year. So we're two calls away from giving you an outlook for 2023.
Phil Cusick -- J.P. Morgan -- Analyst
I guess. Thank you.
Oper