Barry A. Hytinen
Executive Vice President and Chief Financial Officer at Iron Mountain
Thanks, Bill, and thank you all for joining us today to discuss our fourth quarter and full year 2023 results and our outlook for 2024. Turning to our financials. In the fourth quarter, our team continued the trend of delivering record performance on all of our key financial metrics. On a reported basis, revenue of $1.42 billion grew 11% year-on-year or 10% on a constant currency basis, reflecting a new quarterly record. On an organic basis, total organic revenue grew 8.7%. A key highlight in the quarter is our organic storage revenue, which grew 10.4% as a result of strong performance in both our records management and our data center businesses. Total service revenue increased 8% to $549 million.
This was driven by global RIM at 10% on a reported basis and 9% on an organic basis. Project Matterhorn's focus on selling our entire range of products and services has driven these strong results and are a testament to our commercial team's efforts. Adjusted EBITDA was $525 million, a new record, up 11% on a reported basis and 10% year-on-year on a constant currency basis. Adjusted EBITDA margin was better than we projected at 37% and improved 100 basis points sequentially driven by strong mix and cost productivity across all of our businesses. As we've stated in our earnings press release, effective in the fourth quarter of 2023, our AFFO definition has been updated to exclude amortization of capitalized commissions.
In light of the growth of our data center business, we conducted a benchmarking analysis of other companies in the industry, and as such, have aligned our AFFO reporting accordingly, which provides investors better insight into the funds available to support the growth of our business. AFFO was $328 million or $1.11 on a per share basis, up $29 million and $0.09, respectively, from the fourth quarter of last year. To allow for comparison to our guidance and consensus, we are reporting our prior methodology as well. On our previous calculation, AFFO was $317 million or $1.07 on a per share basis. This was $7 million better than our AFFO guidance and $0.02 better than our guidance on a per share basis. Now let me briefly summarize the full year. Revenue of $5.5 billion increased 7% on a reported basis and 8% on a constant currency basis.
Adjusted EBITDA increased 7% year-on-year to $1.96 billion, an increase of $135 million. AFFO increased over 5% to $1.2 billion or $4.12 on a per share basis. On our previous calculation, AFFO was $1.168 billion or $3.97 on a per share basis. And now turning to segment performance for the quarter. Our global RIM business delivered revenue of $1.19 billion, an increase of $108 million from last year or 10% on a reported basis. On an organic constant currency basis, revenue increased 8.5%. Global RIM adjusted EBITDA was $534 million, an increase of $48 million year-on-year. Global RIM adjusted EBITDA margin was 44.7%, up 100 basis points sequentially, driven by strong services mix and productivity.
Our data center business continues to grow and deliver strong performance. From a total revenue perspective, we delivered 32% year-on-year growth on a reported basis and 30% year-on-year growth on a constant currency basis. Our data center storage revenue grew 34% year-on-year or 32% on a constant currency basis, driven by new development coming online. Data center EBITDA was up approximately $10 million year-on-year, and EBITDA margin was up 80 basis points sequentially. Moreover, pricing trends have continued to be strong, and we have seen returns expanding 100 to 150 basis points in advance of higher interest rates. Turning to new and expansion leasing. We completed four megawatts in the fourth quarter.
For the full year, we leased 124 megawatts, exceeding the projection we provided on our last call. Nearly 100% of those leases resulted from cross-selling, which you know is a key initiative in our Project Matterhorn plan. Our pipeline is at record levels. We are expanding our relationships with key hyperscale clients and our team is executing well. So we are pleased to project new and expansion leasing of 100 megawatts for 2024. Incidentally that represents a 25% increase from our initial 2023 projection at this time last year. Turning to our asset life cycle management business. In the fourth quarter, we delivered improved performance for both revenue and EBITDA, achieving the expectations we set on our last call. Our team drove strong operating productivity, and we saw component pricing beginning to trend up modestly on a sequential basis.
Similar to data center, cross-selling activity has been particularly strong in our ALM business with nearly all deals coming in as a result of it. We completed our acquisition of Regency Technologies early in January. This acquisition strengthens our ability to serve an expanding ALM customer base and broadens our capability in their category, especially in the enterprise segment. Regency brings robust remarketing and recycling capabilities to better serve our customers and help them achieve their environmental and data security goals. We have long admired the leadership at Regency and are thrilled to welcome their entire organization to our team.
Turning to capital. For the full year 2023, we invested $1.2 billion of growth and $140 million of recurring, consistent with the expectations we shared on our last call. For 2024, we are planning for capital expenditure to be approximately $1.35 billion of growth and approaching $150 million of recurring. Given our strong pre-lease activity, the vast majority of our growth capital will be dedicated to data center development. Turning to the balance sheet. With strong adjusted EBITDA performance, we ended the quarter with net lease adjusted leverage of 5.1 times and our leverage remains at its lowest level in a decade. For 2024, we expect to exit the year at similar levels to year-end 2023. Our Board of Directors declared our quarterly dividend of $0.65 per share to be paid in early April.
And on a trailing four-quarter basis, our payout ratio is now 62%, in line with our long-term target range of low to mid-60s percent. Now let me provide an update on our progress as to the project Matterhorn growth objectives we shared at our Investor Day in September of 2022. You will recall that we introduced tighter targets for growth between the period 2021 through 2026 of approximately 10% for revenue, approximately 10% for adjusted EBITDA and approximately 8% for AFFO. Two years into our Matterhorn journey, we are well on track, even ahead of those commitments, having achieved 13% annual revenue growth from 2021 to the end of 2023 on a constant currency basis. we have achieved 11% annual adjusted EBITDA growth and in excess of 10% annual AFFO growth.
The dollar has been particularly strong over this period and despite this, we have been delivering on our commitments on a reported basis as well. Now let me share our projections for the full year 2024. We expect total revenue to be within the range of $6 billion to $6.15 billion, which represents year-on-year growth of 11% at the midpoint. We expect adjusted EBITDA to be within the range of $2.175 billion to $2.225 billion, which represents year-on-year growth of 12% at the midpoint. We expect AFFO to be within the range of $1.3 billion to $1.335 billion, which represents year-on-year growth of 9% at the midpoint. And we expect AFFO per share for the full year to be $4.39 to $4.51 and this represents year-on-year growth of 8% at the midpoint.
In terms of foreign exchange, we are using a forecast based on those of several major financial institutions compared to 2023, this results in a full year FX headwind of $25 million of revenue and approximately $10 million to EBITDA and AFFO. Turning to the first quarter. We expect revenue of approximately $1.45 billion, adjusted EBITDA in excess of $510 million and AFFO of approximately $310 million and AFFO per share of approximately $1.05. To conclude, we are pleased to have delivered a strong year in 2023. I am confident that we will build on our momentum and continue to drive strong growth in 2024. We are well on track to achieve our Project Matterhorn goals. I'd like to take this opportunity to express my thanks to our entire team for delivering a successful year and their continued dedication to serving our clients.
And with that, operator, will you please open the line for Q&A?