You are given a text that consists of multiple sentences. Your task is to perform abstractive summarization on this text. Use your understanding of the content to express the main ideas and crucial details in a shorter, coherent, and natural sounding text. 
Text: As we have navigated the last two years, we have learned to operate in highly uncertain and volatile environment.
And we have done it with success on almost any metric.
We've had to accomplish our mission while keeping our people safe.
Our company values of Mission First People always have served us extremely well throughout these unprecedented times.
We had an exceptional third quarter at EMCOR, especially against a very difficult comparison in the prior year.
As you may recall, in the third quarter of last year, we were bringing about a third of our company back to full operations.
We had projects poised and ready to resume or start, delay service that needed to be completed.
And buildings, campuses and production facilities that we helped our customers reopen as they resumed operations.
Further, we had yet to bring back our full complement of staff that we need to sustain and build our operations.
Said simply, we had an abundance of work had all the materials and a lower cost base, as we were still returning to full operations after the extreme cost reductions we had taken in response to the pandemic.
Against that backdrop in comparison for the third quarter of 2021, we were able to post $1.85 and earnings per diluted share, versus $1.76 of adjusted diluted earnings per share in the year ago period.
We grew revenues to $2.52 billion, with 14.5% overall revenue growth and 12.2% organic revenue growth.
We posted 5.4% operating income margins despite strong headwinds from supply chain issues and labor disruptions caused by the Delta Variant.
I believe this is very good performance considering the operating conditions we faced in the quarter.
We grew remaining performance obligations or RPOs 18.7% from the year ago period to $5.38 billion.
We generated operating cash flow of $121 million, despite the strong organic revenue growth.
All-in-all, we had a very successful quarter that continues to show the strength and diversity of our business.
But more importantly, the outstanding leadership provided by our teams at the subsidiary, segment and corporate level.
Our electrical and mechanical construction segments had excellent performance in the third quarter of 2021.
Both segments posted strong operating income margins, and had strong organic revenue growth.
Through careful planning on our large projects, and excellent supplier relationships we mitigated a lot of the supply chain disruptions facing our operations.
However, we have seen cost increases of 10% to 20% and anticipate that such increases will continue in the near future.
And that is only part of the issue, as we have seen lead times increased by two to three times their normal levels.
Our success in the quarter points to the continued resiliency of our teams, the ability to navigate these issues, deliver for our customers and continue to keep our workforce productive and safe.
We continue to have a robot pipeline of data center, warehousing and healthcare projects.
And we had strong bookings with our manufacturing clients in the quarter.
Building Services had the most difficult comparison a quarter as a deep cost cuts taken at the height of the shutdown were most severe in the segment.
We still post a decent operating income marked as a 5% against the year ago period of 6.9%.
However, we were most affected in this segment by supply chain issues and diminished productivity.
Although demand for our retrofit project work is very strong, we had some issues with a synchronization of our supply chain with our labor planning, resulting in reduced productivity.
To mitigate these issues, it has become a common practice that daily communications on deliveries and price changes on our quick term project and service work.
Further, this segment also bears the brunt of the dollar per gallon increase in the fuel, which gasoline and diesel year-over-year due to its large fleet and this had an impact of 20 to 30 basis points on operating income margins.
We can pass some of this increase on our customers that had just repriced into our time and material rates in June.
We will do so again between now and January across the majority of our building services operations.
This is the second increase this year, which is not our usual practice of executing which is once a year, usually in June.
Demand remained strong and we will continue to improve our planning over the next quarter or two.
Industrial Services continue to operate as we expected.
We improved on a year-over-year basis with respect to revenue and operating income.
We had some impact with respect to the storms in the Gulf Coast.
But that mainly just pushed out work to later in the year or into next year.
And we did have some disruption to our shop work in Louisiana.
Demand for our services continues to build.
Refinery utilization is at a very high level.
And we expect to and we expect to execute a better fourth quarter turnaround season this year versus the year ago period.
We also anticipate much improved demand as we exit the year and move into the first quarter of 2022.
The U.K. continues to execute well for its customers with double digit revenue growth and good operating income margins.
Demand remained strong for our services.
But like in the United States, we are also battling supply chain issues for our quick term project work in the United Kingdom.
We'll leave the quarter with a pristine balance sheet, strong fundamentals and record RPOs.
Over the next several slides I will augment Tony's opening commentary on EMCOR's third quarter, as well as provide a brief update on our year-to-date results through September 30.
So let's revisit and expand overview of EMCOR's third quarter performance.
Consolidated revenues of $2.52 billion are up $320 million or 14.5% over Quarter 3, 2020 and represent a new all-time quarterly revenue record for EMCOR.
Each of our reportable segments experienced quarter-over-quarter revenue growth.
Excluding $50.3 million of revenues attributable to businesses acquired, pertaining to the time that such businesses are not owned by EMCOR and last year's quarter, revenues for the third quarter of 2021 increased nearly $270 million or a strong 12.2% when compared to the third quarter of 2020, which was still somewhat impacted by the effects of the COVID-19 pandemic.
The specifics of each reportable segment are as follows: United States Electrical Construction revenues of $527.9 million increased $55.9 million or 11.8% from 2020s third quarter.
Excluding acquisition revenues within the segment of $29.5 million this segment's revenues grew organically 5.6% quarter-over-quarter.
Increased project activity within the commercial healthcare and institutional market sectors were the primary drivers of the period over period improvement.
United States mechanical construction segment revenues of $999.6 million increased $108.1 million or 12.1% from Quarter 3, 2020.
The results of this segment represent a new quarterly revenue record.
Revenue growth during the quarter was driven by increases within the manufacturing, healthcare and commercial market sectors.
With respect to the manufacturing market sector, we are in the early phases of construction on several food processing plants, which will accelerate further as we move into 2022.
From a healthcare market sector perspective, there continues to be greater demand for our services, as we are engaged in a number of projects ranging from mechanical system retrofits to complete installations in both new and existing healthcare facilities.
Lastly, within the commercial market sector, we continue to see strong demand for data center project work given growth in digital storage and cloud computing across the United States.
And we continue to assist our e-commerce customers with the build out of the warehouse and distribution network through both traditional mechanical as well as fire protection services.
Third quarter revenues from EMCOR's combined United States construction business of $1.53 billion increased $164 million or 12%, with 9.9% of such revenue growth being organic.
This combined revenue performance eclipses the quarterly revenue record established by this group during the second quarter of this year.
Despite this record revenue performance, each of our construction segments have increased the remaining performance obligations both year-over-year as well as sequentially.
United States Building Services Quarterly revenues of $632.5 million increased $75.9 million or 13.6%.
Excluding acquisition revenues of $20.8 million the segment's revenues increased at 9.9% organically.
Revenue gains were reported within our mobile mechanical services division due to increase project, service repair and maintenance activities.
Our commercial site based services division as a result of new contract awards, and our government services division given an increase in indefinite delivery indefinite quantity project volumes.
EMCOR's industrial services segment revenues of $232.2 million increased $60.7 million or 35.4% due to improve demand for both field and shop services, as we are beginning to see some resumption of maintenance and small capital spending in the energy sector.
United Kingdom Building Services revenues of $129.5 million increased $19.4 million or 17.6% from last year's quarter.
Revenue gains for the quarter resulted from the continuation of strong project demand from the segment's maintenance customers who previously deferred such work during 2020 as the result of the COVID-19 pandemic in the related prolonged U.K. government lockdown measures.
Additionally, the segment's revenues were positively impacted by $8 million, a favorable foreign exchange rate movements within the quarter.
Selling, General, Administrative expenses of $243.9 million represent 9.7% of third quarter revenues and compared to $226.8 million or 10.3% of revenues in the year ago period.
The current year's quarter includes approximately $5.3 million of incremental expenses from businesses acquired, inclusive of intangible asset amortization, resulting in an organic quarter-over-quarter increase in SG&A of $11.9 million.
Consistent with my commentary during our second quarter earnings call, the prior year period benefited from substantial cost reductions resulting from our actions taken in response to the COVID-19 pandemic.
A significant percentage of such savings pertained to employment costs, including furloughs, headcount, reductions, and temporary salary reductions.
Conversely, EMCOR's considerable revenue growth in 2021 has necessitated an increase in headcount in the current year.
Additionally, our SG&A for the current period reflects an increase in healthcare costs, as the result of a normalization in the level of medical claims, as well as greater travel and entertainment expense due to a partial resumption of certain business activities by our workforce, when compared to the same timeframe in 2020.
The reduction in SG&A as a percentage of revenues as a result of the aforementioned increase in quarterly revenues without a commensurate increase in certain of our overhead costs, as we were able to successfully leverage our cost structure during this period of strong organic revenue growth.
Reported operating income for the quarter of $137.4 million or 5.4% of revenues, compares to operating income of $135.9 million or 6.2% of revenues in 2020's third quarter.
The 80 basis point reduction in operating margin loss due to reductions in gross profit margin within several reportable segments due to a less favorable revenue mix, which I will elaborate on during my individual segment commentary.
Despite this reduction in quarter-over-quarter operating margin, EMCOR's $137.4 million of operating income represent a new third quarter record.
Specific quarterly performance by segment is as follows: Our U.S. Electrical Construction segment operating income of $44.1 million decreased $1.9 million from the comparable 2020 period.
Reported operating margin of 8.3% represents a reduction from the 9.7% margin reported in 2020's third quarter.
The decrease in both operating income and operating margin is due to a decline in gross profit within the commercial and transportation market sectors given a change in the composition of project work performed quarter-over-quarter.
In addition, and as disclosed in last year's third quarter, the results from the prior year period benefited from the settlement of final contract value on two projects, which favorably impacted this segments Q3, 2020 operating income and operating margin by $4.4 million and 70 basis points respectfully.
Third quarter operating income for U.S. Mechanical Construction Services segment of $82.3 million represents a $2.3 million increase from last year's quarter, while operating margin of 8.2% represents an 80 basis point reduction from the 9% earned in 2020's 3rd quarter.
From an operating margin perspective similar to our Electrical Construction segment the reduced profitability can be attributed to a less favorable mix of work during the quarter.
Most notably, this segment experienced a decrease in gross profit margin within the manufacturing market sector, as the results for the period include increased revenues from certain large food processing projects, for which we are for which we are acting as the construction manager and carry lower than average gross profit margins when compared to our traditional subcontractor arrangements with our customers.
Further, the results for the year ago period benefited from the favorable close out of several manufacturing projects, which resulted in incremental operating margin contribution.
To be clear, the impacts within the quarter for both our Construction Segments relate to discrete projects or events.
Our combined U.S. Construction business is reporting $126.4 million of operating income with an 8.3% operating margin.
This level of operating income represents a new third quarter record for our combined construction business.
I would like to add that though below that of the prior year, the operating margins today in 2021 for each of our Electrical and Mechanical Construction segments exceed both their three year and five year average margins.
Operating income for U.S. building services is $31.6 million or 5% of revenues.
This represents a reduction of $6.9 million and 190 basis points of operating margin quarter-over-quarter.
Growth and operating income within the segment's commercial site based and government services divisions was not enough to offset the clients within its mobile, mechanical and energy services divisions.
As I commented during last quarter's call, our Mobile Mechanical Services Division has a large number of fixed price capital projects currently in process, which traditionally have a lower gross profit margin profile than the segments call out service and small project work.
In addition, during the quarter, we experienced some productivity issues partially due to the delayed receipt of certain equipment and materials, which has impacted our profitability both in terms of dollars and margin.
Lastly, growth in the segment's SG&A expenses due to headcount additions to support revenue growth, as well as incremental amortization expense related to businesses acquired further compressed operating income and operating margin.
Our U.S. Industrial Services segment operating loss of $3 million represents a $5.9 million improvement from the $8.9 million loss reported in 2020's 3rd quarter.
Development improvement, this segment continues to be impacted by difficult market conditions within the oil and gas industry.
Additionally, though, not as severe as in the prior year quarter, this segment experienced lost workdays due to both temporary plant and certain customer site closures, resulting from named storm activity in the Gulf Coast region during the 2021 quarter.
U.K. Building Services operating income of $6.6 million or 5.1% of revenues represents an increase of $1.3 million and a 30 basis point improvement and operating margin quarter-over-quarter.
Approximately $400,000 of this period-over-period improvement is due to positive foreign exchange movement, with the remainder attributable to an increase in project activity primarily within the commercial market sector.
We are now on slide nine.
Additional financial items of significance for the quarter not addressed in the previous slides are as follows: Quarter three gross profit of $381.3 million is higher than the comparable quarter by $18.2 million or 5%, gross margin of 15.1% as lower than the 16.5% and last year's third quarter due to the shift in revenue mix in each of our U.S. Electrical and Mechanical Construction segments as well as their U.S. building services segment as I just referenced during my segment operating income discussion.
Diluted earnings per common share of $1.85 represents a new quarterly record for the company and compares to $1.11 per diluted share in last year's third quarter.
Adjusting 2020's earnings per share for the negative impact and our prior year income tax rate resulting from the non-deductible portion of last year's non-cash impairment charges recorded during 2020 second quarter.
Non-GAAP diluted earnings per share for the quarter ended September 30, 2020 was $1.76 when compared to our current quarter's performance, we are reporting a $0.09 or 5.1% quarter-over-quarter earnings per share improvement.
With my quarter commentary complete, I will touch on some high level highlights with respect to EMCOR's results for the first nine months of 2021.
Revenues of $7.26 billion represent an increase of $747.8 million, or 11.5%, of which 9.4% of such revenue growth was generated by organic activities.
Operating income of $387.8 million or 5.3% of revenues represents a significant increase from reported operating income for the first nine months of 2020 and a double digit increase from the corresponding adjusted non-GAAP operating income figure for that period.
Year-to-date diluted earnings per share is $5.17 and represents an increase of approximately 14% over 2020's adjusted non-GAAP earnings per share for the nine month period.
Although not shown on the slide, my last comment on our year-to-date results is with respect to operating cash flow.
For the first nine months of 2021, we have generated approximately $114 million of operating cash flow, which is well below 2020s record performance.
As I commented last quarter, our substantial organic revenue growth has required increased working capital investment.
This contrast to 2020 where for a large part of the year, we were liquidating our balance sheet due to the revenue declines resulting for the from the COVID-19 pandemic.
Further, it is important to note that last year's nine month operating cash flow was favorably impacted by $82.3 million due to government stimulus measures that allow for the deferral of certain tax payments in both the United States and the United Kingdom.
As previously communicated, my expectation for full year 2021 was operating cash flow in excess of $300 million.
With our upward revision in 2021 revenue expectations, I am still targeting the same level of operating cash flow performance, but it is possible that we may not eclipse the $300 million target should our working capital investment be greater than expected during the fourth quarter.
EMCOR's balance sheet remains strong and liquid.
Cash on hand is down from year-end 2020 driven by cash used in financing activities are approximately $213 million, inclusive of $183 million used for the repurchase of our common stock and cash used in investing activities of $137.5 million, most notably due to payments for acquisitions that have cash acquired totaling approximately $114 million.
These uses of cash were partially offset by cash provided by operations of $114 million as I noted just a few moments ago.
Working capital has increased by nearly $20 million.
Increases in accounts receivable on contract assets resulting from our substantial organic revenue growth during the period were partially offset by the decrease in our cash balance just referenced as well as our increase in contract liabilities.
The increase in goodwill is predominantly a result of the five businesses acquired during the first nine months of this year.
Net identifiable intangible assets increased by $19 million as the impact of additional intangible assets recognize the connection with the previously referenced acquisitions which was largely offset by $48 million of amortization expense during the year-to-date period.
As a reference point, on a full year basis we anticipate depreciation and amortization expense, including both depreciation of property, plant and equipment, as well as amortization of intangible assets to be approximately $112 million for 2021.
Total debt exclusive of operating lease liabilities is fairly consistent with that of December 2020.
And EMCOR's debt-to-capitalization ratio has reduced to 11.4% from 11.9% at year-end, 2020.
EMCOR remains well positioned to capitalize on available opportunities as our balance sheet, combined with the borrowing capacity available to us under our credit agreement provides us with great flexibility and pursuing numerous organic and strategic investments.
I would like to give a call back to Tony, Tony?
And I'm going to be on page 12 remaining performance obligations by segment and market sector.
We had another strong project bookings quarter here at EMCOR.
Each of our five reporting segments are RPO growth year-over-year, while as we mentioned earlier, simultaneously increasing revenue over the same period.
We also saw RPO growth in seven of the eight market sectors in which we report.
So it's fair to say that we're currently seeing strong future demand across all of our segments and market sectors.
While September 30, is a single point in time, and project certainly ebb and flow, we are well positioned moving into 2022.
As mentioned earlier, total company RPOs at the end of the third quarter were just under $5.4 billion, up $849 million or 18.7% when compared to the year ago level of $4.5 billion.
Organic RPO growth was strong 15.6%.
Year-to-date for the nine months completed in 2021 total RPOs have increased $784 million, or just over 17%.
The strong booking activity across the company trends related to a book-to-bill ratio well over one, despite the company generating record revenues.
Our two domestic construction segments experienced strong construction project growth in the quarter, with RPOs increasing $606 million or 16.5% from the same period last year.
RPOs were lifted slightly by two Midwestern Electrical Construction Services acquisitions completed this year.
Building Services or RPO levels increased 180 million or almost 29% from the year ago quarter, 142 million and 180 million was organic.
We continue to see widespread small and short duration project demand and believe this will remain active through the end of the year and into 2022 as workers returned to buildings, campuses, factories and institutional facilities across the country post COVID and as the Delta variant hopefully continues to subside.
Our Industrial Services segments, our RPO increase of $53 million from September 2020.
Work within our heat exchanger shops has been building and while still are lower than historical levels, pricing appears to be improving a bit.
Further, we continue to build capability, execute fixed price contract work, in both our electrical and mechanical trades in this segment.
While this segment remains challenged due to macroeconomic forces, we are starting to see signs of increased activity, much as we expected as we move into 2022 and that is good news.
In summary, we continue to see strong momentum in our core markets and our scale, diversity of demand, and ability to pivot to more resilient sectors has allowed us to continue to have strong bookings in RPO growth, but also very strong organic revenue growth.
I'm now going to finish our discussion on pages 15 and 16.
We are closing in on yet another record year performance at EMCOR despite a very difficult operating environment.
At the beginning of the year, we expected that margins would be under some pressure.
But we believe that we would have the necessary revenue growth to offset any margin compression.
We foresaw the supply chain issues, but quite frankly, they are worse than we expected.
We not only have seen increasing and volatile pricing, but lead times that extend through two to three times normal levels.
Energy prices, especially gasoline and diesel costs have increased by more than we anticipated.
We also expect COVID to be much less impactful than it was as a Delta variant caused disruption on some job sites and send some key supervision into quarantine.
Working in this challenging environment, we continue to deliver in a no excuses manner and execute well for our customers while keeping our employees safe.
Despite such headwinds, we are raising our guidance.
Our new guidance is diluted earnings per share of $6.95 to $7.15 and we now expect our revenues between $9.80 billion and $9.85 billion.
As we close on 2021, we do expect to continue to be challenged by supply chain and productivity issues.
But we will work through them as we are resilient.
We expect the non-residential market to show mid-single digit growth in 2021 and expect that momentum to continue into 2022.
We, like all large employers will have to navigate complying with the pending emergency temporary standard or ETS with respect to mandatory vaccination and testing and the executive order mandating vaccination on federal contracts.
The ETS has not been released and therefore the related costs to comply and the impact to our productivity are unknown.
We expect to energy generate additional operating cash flow in the fourth quarter.
And we expect to continue to be balanced capital allocators.
To date into 2021, we have repurchased $183 million in EMCOR stock, paid $21 million in dividends and invested $114 million in acquisitions that will continue to position EMCOR for long term and sustained growth.
Our board of directors just authorized a new and our largest share repurchase authorization of an additional $300 million.
We continue to have a very active acquisition pipeline.

user
emcor group q3 revenue rose 14.5% to $2.52 billion.
q3 earnings per share $1.85.
q3 revenue rose 14.5 percent to $2.52 billion.
sees fy earnings per share $6.95 to $7.15.
sees fy revenue $9.8 billion to $9.85 billion.
authorizes additional $300 million share repurchase program.

assistant