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Text: These include all statements reflecting Quanta's expectations, intentions, assumptions or beliefs about future events or performance that do not rely -- solely relate to historical or current facts.
Please also note that we will present certain historical and forecasted non-GAAP financial measures in today's call, including adjusted diluted EPS, backlog, EBITDA and free cash flow.
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Backlog at the end of the quarter was a record $15.8 billion, which we believe reflects the continued advancement of our long-term growth strategies.
We continue to see opportunities for multi-year growth across our service lines, driven by our solutions-based approach and the growth of programmatic spending with existing and new customers.
The recognition that the country's infrastructure needs to be modernized to support economic growth improved safety and reliability and for a cleaner environment is evidenced by the Biden administration's recently proposed $2 trillion infrastructure plan.
The proposal will evolve and take time to move through the political process.
But as proposed, the plan includes funding and policies to encourage new infrastructure development and modernization in several of our core markets including, high-voltage electric transmission and power grid modernization and resiliency, renewable energy, electric vehicle charging station infrastructure and other electrification initiatives, and broadband infrastructure expansion.
While this infrastructure proposal could accelerate activity in these areas and provide incremental opportunity for Quanta over several years, I want to stress that our positive multiyear outlook and strategic plan are not reliant on this infrastructure proposal.
We have been collaborating with our customers for many years to support their significant multiyear investment programs already in place to modernize the existing power grid, ensure reliable power delivery and to integrate higher levels of renewable generation.
Our Electric Power Solutions operations performed well during the quarter, reflecting broad-based business strength, driven by ongoing grid modernization, system hardening, renewable energy interconnections and solid and safe execution.
During the quarter, we signed a significant multiyear master services agreement with a utility in the Western United States, which made a substantial incremental contribution to our record first quarter backlog.
We believe our record backlog and these initiatives will continue to drive multiyear growth opportunities for Quanta.
Though COVID-19 has created some near-term challenges in Canada, we see opportunities to pursue additional large projects there for the coming years.
Additionally, our discussions with high-voltage electric transmission project sponsors in the United States have increased as the need for large-scale electric transmission infrastructure to support growing renewable generation and achieve carbon-neutrality goals become evident.
LUMA Energy and its employees, as supported by Quanta and its joint venture partner ATCO, are all working diligently toward transitioning the operations and maintenance of the Puerto Rico electric power grid to LUMA in early June.
LUMA's efforts under the agreement are intended to deliver long-term social and economic benefits to the people of Puerto Rico.
As stated previously, we believe this opportunity is transformative for all the parties involved, including the people of Puerto Rico, and the work to be performed by LUMA under the 15-year contract aligns with Quanta's strategy of providing sophisticated and valuable solutions to the utility, industry that benefits consumers.
The majority of our communications operations are off to a solid start this year, driven by strong demand for fiber densification to reach homes and businesses and the early stages of 5G network deployments.
However, during the quarter, we experienced short-term challenges really associated with efficient subcontractor work in a specific geographic area, which required rework.
We have addressed our quality assessment protocol shortcomings on this issue and are pursuing compensation from the subcontractor.
This was an isolated issue, and we believe we are on track to generate high-single or double-digit operating income margins for the remainder of this year.
Additionally, we continue to believe, we can achieve at least $1 billion in annual revenue with double-digit operating income margins in the medium term.
As service providers continue to push fiber closer to the customer, fiber backhaul densification continues, 5G wireless infrastructure development increases, and meaningful federal funding is provided for broadband network expansion initiatives in underserved markets.
On prior calls, we have shared our belief that Quanta is uniquely positioned between the communications and utility industries to provide solutions for broadband and 5G technology deployments leveraging existing infrastructure.
We have made significant progress working with our customers and a broadband technology partner and during the first quarter made a minority financial investment in this partner.
We also entered into a strategic alliance with them where Quanta will serve as a program manager for large-scale deployments of their fixed wireless broadband technology which we utilized our customers' facilities where appropriate.
We believe this relationship advances our solutions with customers to accelerate and improve access to affordable and reliable broadband in rural and underserved markets.
We believe our proactive strategy and the unique solutions Quanta provides the marketplace enhances our opportunity to expand our telecom infrastructure solutions with other utility and communication customers.
Our Underground Utility and Infrastructure Solutions segment performed well in the quarter with better than expected profitability despite seasonality and continued challenges caused by COVID-19.
We are confident in our full year expectations for the segment driven by solid demand for our gas utility and pipeline integrity service.
Additionally, there are encouraging signs supporting our expectations of improved demand for our industrial services beginning in the second half of this year.
We believe deferred maintenance and capital spending due to the effects of COVID on the downstream market is creating pent-up demand for our services which should prove beneficial as market conditions normalize for our customers.
However, we would like to see how the summer travel season develops which could influence activity levels of our downstream customers before making adjustments to our full year expectations for this segment.
The solutions Quanta provides support our customers' efforts to increase reliability, safety, efficiency, and connectivity all of which have favorable, environmental, and social impact.
Our end markets and multiyear visibility are solid and we have built a strong platform that positions us well to capitalize on favorable long-term trends particularly grid modernization and hardening, the transition toward a carbon-neutral economy, and the adoption of new technologies such as 5G, battery storage, and hydrogen.
Previously, we have discussed our strategic focus on enhancing our front-end capabilities such as engineering and permitting.
To complement our world-class construction expertise, our strategy is designed to provide differentiated comprehensive and industry-leading solutions to our customers which we have achieved through organic investment and select acquisitions.
This strategy is contributing to our backlog growth increasing our total addressable market and providing meaningful growth opportunities for the future.
We believe this demonstrates the strength and sustainability of our business and long-term strategy, favorable end market trends, our ability to safely execute, and our strong competitive position in the marketplace.
We continue to believe we are in a multiyear up cycle with continued opportunity for further record backlog and results in 2021.
We are focused on operating the business for the long-term and expect to continue to distinguish ourselves through safe execution and best-in-class build leadership.
We will pursue opportunities to enhance Quanta's base business and leadership position in the industry and provide innovative solutions to our customers.
We believe Quanta's diversity unique operating model and entrepreneurial mindset form the foundation that will allow us to continue to generate long-term value for all our stakeholders.
Today we announced first quarter 2021 revenues of $2.7 billion.
Net income attributable to common stock was $90 million or $0.62 per diluted share and adjusted diluted earnings per share a non-GAAP measure was $0.83.
The first quarter was another strong quarter for Quanta led by continued strength from electric power and better-than-expected profitability from our Underground Utility and Infrastructure segment.
Our electric power revenues were $2.1 billion a record for the first quarter and a 17% increase when compared to the first quarter of 2020.
This increase was driven by continued growth in base business activities as well as contributions from larger transmission projects under way in Canada and revenues from acquired businesses of approximately $70 million.
Also revenues associated with emergency restoration services attributable to winter storm response efforts were approximately $80 million a first quarter record.
Electric segment margins in 1Q 2021 were 9.7% versus 7.3% in 1Q 2020.
The improved operating margins were driven by double-digit performance from our electric operations within the segment including the benefit associated with increased profit contributions from emergency restoration efforts, which typically present opportunities for higher margins than our normal base business activities due to higher utilization.
Operating margins also benefited from approximately $5 million of income associated with our LUMA joint venture.
Negatively impacting first quarter margins were recorded reserves for the identified issues Duke discussed, which when combined with normal seasonality exacerbated by severe weather challenges from winter Storm Uri created an operating loss within our US telecom operations for the quarter.
Again we believe we have addressed the issues and expect margins at or near double-digits going forward.
Underground Utility and Infrastructure segment revenues were $643 million for the quarter, 35% lower than 1Q 2020 due primarily due to reduced revenues from our industrial operations and a reduction in contributions from larger pipeline projects.
Operations within this segment in last year's first quarter results had yet to be impacted by COVID-19 headwinds.
And in fact our industrial operations had record results in the period.
In 1Q 2021, the segment continues to be negatively impacted by COVID-19 with first quarter revenues from our Canadian operations and our industrial operations both meaningfully below pre-pandemic levels.
Despite the COVID-related headwinds, the segment delivered margins of 1.4%.
And although 170 basis points lower than 1Q 2020 primarily due to the reduced revenues, the results exceeded our original expectations for 1Q led by execution across much of our base business activity including our gas distribution and industrial services.
Our total backlog was a record $15.8 billion at the end of the first quarter with 12-month backlog of $8.9 billion representing solid increases when compared to year end as well as the first quarter of 2020.
This marks the third consecutive quarter where we posted record backlog, a trend driven primarily by continued growth in multiyear MSA programs with North American utilities which we believe continues to validate the repeatable sustainable nature of the largest portion of our revenues and earnings.
For the first quarter of 2021, we generated free cash flow, a non-GAAP measure of $49 million, $115 million lower than 1Q 2020, however 1Q 2020 included the collection of $82 million of insurance proceeds associated with the settlement of two pipeline project claims.
Day sales outstanding or DSO measured 89 days for the first quarter, an increase of four days compared to the first quarter of 2020 and an increase of six days compared to December 31, 2020.
These increases are primarily due to the expected ramp in work on two larger electric transmission projects in Canada in the first quarter and the timing of billing.
The Canadian response to COVID has significantly hampered production for which we will seek recovery and delayed this in meeting certain billing milestones.
We had approximately $200 million of cash at the end of the quarter with total liquidity of approximately $2.1 billion and a debt-to-EBITDA ratio as calculated under our credit agreement of approximately 1.3 times.
Integration activities associated with acquisitions closed in the back half of 2020 are ongoing and we closed another small acquisition during the first quarter of 2021.
We continue to take an opportunistic view toward acquisitions and maintain the balance sheet strength to support strategic capital outlays in this area.
We remain committed to delivering shareholder value through prudent capital deployment.
Based on the Electric segment's strong first quarter and continued confidence in our ability to execute on the opportunities across the segment, we've increased the low end of our full year expectations for segment revenues resulting in a range between $8.4 billion and $8.5 billion for 2021.
Similarly, we are increasing the low end of our full year margin range for the segment with 2021 operating margins now expected to range between 10.2% and 10.9%.
Regarding the Underground Utility and Infrastructure Solutions segment, while we had a nice start to the year, we are not yet in a position to change our full year expectations.
Accordingly, we are reiterating our original full year guidance for the segment with revenues expected to range between $3.65 billion and $3.85 billion and segment margins ranging between 5.5% and 6%.
These segment operating ranges support our increased expectations for 2021 annual revenues of between $12.05 billion to $12.35 billion and adjusted EBITDA, a non-GAAP measure of between $1.1 billion and $1.2 billion.
The midpoint of the range represents 10% growth when compared to 2020's record adjusted EBITDA.
In addition to these improved operating expectations, our full year expectations for net income and adjusted net income, a non-GAAP measure are expected to benefit from a reduced annual tax rate, driven by higher benefits realized in the first quarter associated with the fair value of vested stock compensation awards.
We now expect our full year tax rate to range between 25.25% and 25.75%.
As a result, our increased expectation for full year diluted earnings per share attributable to common stock is now between $3.25 and $3.69, and our increased expectation for adjusted diluted earnings per share attributable to common stock a non-GAAP measure is now between $4.12 and $4.57.
We are maintaining our free cash flow guidance for the year, expecting it to range between $400 million and $600 million.
And we'll reiterate that quarterly free cash flow is subject to sizable movements due to various customer and project dynamics that can occur in the normal course of operations.
Overall, we are pleased with the start to the year and remain confident in the strength of our operations and prospects for profitable growth.
As our backlog continues to grow and our visibility into the duration of this infrastructure cycle continues to improve, we have increasing conviction in our ability to capitalize on the opportunities across our end markets.
We firmly believe the repeatable nature of our base business solutions coupled with opportunistic larger project deployments, disciplined capital allocation and continued balance sheet strength will be the key to delivering long-term shareholder value.

user
compname reports q1 gaap earnings per share $0.62.
q1 adjusted non-gaap earnings per share $0.83.
q1 gaap earnings per share $0.62.
q1 revenue $2.7 billion versus $2.76 billion.
long-term outlook for quanta's business is positive.
expects 2021 revenues to be between $12.05 billion and $12.35 billion.
sees fy diluted earnings per share attributable to common stock $3.25 and $3.69.
sees fy adjusted diluted earnings per share attributable to common stock $4.12 and $4.57.

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