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 you saw yesterday, we reported a really strong performance out of the gate in '21 and what's shaping up to be a great year.
We knew we had built good momentum in Q4 and that the economy was moving in the right direction.
But the first quarter was still uncertain as we ended the year, while not anymore, both our operating conditions and our performance have improved faster than we expected.
We gained back a lot of the ground on the rental revenue, narrowing the decline from 2020 and importantly, we exited the quarter up year-over-year in March.
Our customers are also optimistic.
They're gaining more visibility and they're turning to us for the equipment they need.
Just a few months into the year, we've absorbed almost all of the excess fleet we had in 2020.
This was evident in the sequential improvement in our fleet productivity that we reported.
And we took advantage of a healthy used-equipment market driving record retail sales to generate almost 30% more proceeds in the quarter than we did a year ago.
None of this would be possible without our greatest asset, our employees and their willingness to take on the challenges as well as the opportunities presented to them.
A lot of people know how much I respect them for their commitment and our customers feel the same way.
And I'm proud to report the team United delivered $873 million of adjusted EBITDA in the first quarter and they did it safely turning in another quarterly recordable rate below one.
Given all these factors, we feel confident in raising guidance across the board.
This includes a new revenue range that starts above the top end of the previous guidance.
We feel equally comfortable leaning into M&A as evidenced by our recent acquisition of Franklin Equipment and our agreement to acquire General Finance, which we expect to close mid-year.
We feel the time is right to allocate capital to attractive deals like these that meet our M&A criteria for a strong strategic, financial and cultural fit.
With Franklin, we added 20 stores to our General Rental footprint in the Central and Southeast regions.
General Finance is a market leader in mobile storage and modular office rentals.
And these services complement our current specialty in gen rent offerings and we're excited about the opportunity to unlock additional growth while solving more of our customers' needs with these new products.
We'll be entering these markets with a strong presence and established footprint and a talented team with solid customer relationships, many of them new to our company.
It's a textbook example of one plus one equaling more than two.
Now let us pivot to demand, where we have more good news to share.
The rebound we are seeing in our end markets is broadly positive.
And this is true of our General Rental business, and even more so in our Specialty segment.
Specialty had another robust performance led by our Power & HVAC business.
Rental revenue for Specialty moved past the inflection point and it was positive year-over-year for the full quarter.
And we're continuing to invest in growing our specialty network with six cold starts year-to-date and another 24 planned this year.
And now I'll drill down to our customers and our end markets.
Customer sentiment continues to trend up in our surveys, as a majority of our customers expect to see growth over the next 12 months.
And importantly, the percent of customers who feel this way has climbed back to pre-pandemic levels.
And we think there are few reasons for this.
For one thing, our customers have a significant amount of work-in-hand and they can also see that our project activity is continuing to recover.
The vaccines are rolling out, restrictions are easing in most markets, and the weather is turning warmer.
Three positive dynamics converge in right before our busy season.
Also we're seeing the return of activity in the manufacturing sector after more than a year of industrial recession.
And the construction verticals that have been most resilient throughout COVID are still going strong, areas that we've discussed like technology and data centers, power, healthcare, and warehousing and distribution.
And with infrastructure, our customers are encouraged that it's back on the table in Washington.
Most of the infrastructure categories and the administration's current proposal are directly in our wheelhouse, things like bridges, airport and clean energy.
And we'll see how the process goes, but almost any infrastructure spending will benefit us in the long term both directly and indirectly.
Now there are some markets that are taking longer to recover, like energy.
Most parts of the energy complex including downstream remains sluggish.
Additionally, retail office and lodging are largely in limbo.
So while we are firing on all cylinders at United, there are pockets of the economy that are still catching up and this means more opportunity for us down the road.
I'll sum up my comments with this perspective.
2021 is shaping up to be a promising year and our performance, says a lot about our willingness to lean into that promise, whether it's with capex, M&A, cold starts or other strategic investments in the business.
Our balance sheet and cash flow give us the ability to keep every option on the table.
Throughout last year, we made the decision to retain capacity by keeping our branch network and our team intact.
And now at the end -- the economic indicators are flashing green.
Our strategy is paying off by driving value for our people, our customers and our shareholders.
And with that, I'll ask Jess to take you through the numbers, and then we'll go to Q&A.
Over to you, Jess.
The strong start to the year is reflected in our first quarter results as rental revenue and used sales exceeded expectations and costs were on track, that strength carried through to our revised guidance and more on that in a few minutes.
Let's start now with the results for the first quarter.
Rental revenue for the first quarter was $1.67 billion, which was lower by $116 million or 6.5% year-over-year.
Within rental revenue, OER decreased $117 million or 7.7%.
In that a 5.7% decline in the average size of the fleet was a $87 million headwind to revenue.
Inflation of 1.5% cost us another $24 million and fleet productivity was down 50 basis points or a $6 million impact.
Sequentially fleet productivity improved by a healthy 330 basis points recovering a bit faster than we expected.
Finishing the bridge on rental revenue this quarter is $1 million in higher ancillary and rerent revenues.
As I mentioned earlier, used equipment sales were stronger than expected in the quarter, coming in at $267 million, that's an increase of $59 million or about 28% year-over-year, led by a 49% increase in retail sales.
The end market for used equipment remained strong and while pricing was down year-over-year, it's up for the second straight quarter with margins solid at almost 43%.
Notably, these results in used reflect our selling over seven year old fleet at around half its original cost.
Let's move to EBITDA.
Adjusted EBITDA for the quarter was just under $873 million, a decline of $42 million or 4.6% year-over-year.
The dollar change includes an $84 million decrease from rental, in that OER was down $86 million, while ancillary and rerent together were an offset of $2 million.
Used sales were tailwind to adjusted EBITDA of $19 million, which offset a $2 million headwind from other non-rental lines of business and SG&A was a benefit in the quarter up $25 million as similar sales the last couple of quarters.
The majority of that SG&A benefit came from lower discretionary costs mainly T&E.
Our adjusted EBITDA margin in the quarter was 42.4%, down 70 basis points year-over-year and flow through as reported was about 62%.
I mentioned two items to consider in those numbers.
First, as I mentioned in our January call, we'll have a drag in bonus expense during 2021, as we reset to our plans target of that reset started in the first quarter.
Second, used sales made up a greater portion of our revenue this quarter, which was a revenue mix headwind.
Adjusting for those two results is an implied detrimental flow through for the quarter of about 37%.
Across the core business, the first quarter's cost performance played out as we expected and reflects our continued discipline as we respond to increasing demand and is our costs continue to normalize.
Our shift to adjusted EPS, which was $3.45, that's up $0.10 versus Q1 last year, primarily on lower interest expense and a lower share count.
Quick note on capex.
For the quarter gross rental capex was $295 million.
Our proceeds from used equipment sales were $267 million, resulting a net capex in Q1 of $28 million.
Now turning to ROIC, which remained strong at 8.9%.
As we look back over what's obviously been a challenging 12 months.
One of the things that we're most pleased with is the ROIC we've generated, which has consistently run above our weighted average cost of capital through what was the trough of the down cycle.
Free cash flow was also strong at $725 million for the quarter.
This represents an increase of $119 million versus the first quarter of 2020 or about a 20% increase.
As we look at the balance sheet, net debt is down 21% year-over-year without having reduced our balance by about $2.3 billion over those 12 months.
Leverage continues to move down and was 3 times at the end of the first quarter, that compares with 2.5 times at the end of the first quarter last year.
Liquidity remains extremely strong.
We finished the quarter with over $3.7 billion in total liquidity that's made up of ABL capacity of just under $3.2 billion and availability on our AR facility of $276 million.
We also had $278 million in cash.
And since Matt mentioned our acquisitions earlier, I'll take a second here to note that we expect to fund the General Finance deal later this quarter with the ABL.
This update does not include any impact from General Finance.
If we close as expected in June, we'll update our guidance likely on our Q2 call in July to reflect the impact of that business.
What is included in this update is mainly three things.
First, the impact of higher rental revenue.
Second, increased used sales capitalizing on a stronger than expected retail market.
And third, the contribution of our Franklin Equipment acquisition, which we estimate at about $90 million of revenue and $30 million of adjusted EBITDA for the remainder of the year.
We revised our current view to rental revenue given the start to the year and how we expect things to play out from here.
The increase in our guidance reflects a range of possibilities with a growth opportunity over the remainder of the year, largely follows normal seasonality, albeit from a higher starting point.
And as you can see at midpoint, our updated guidance implies strong double-digit growth over the remaining nine months of the year.
A quick note on the guidance change in EBITDA and what hasn't changed in this revision, which is our continuing to manage costs tightly even as activity ramps more than forecasted.
Our revised range on adjusted EBITDA considers that cost performance across the core business, and reflects the impact of higher used sales and the Franklin acquisition with margins and flow through in line with our prior guidance.
A certain of our costs continue to normalize from low levels in 2020.
Bonus expense remains the headwind we've discussed previously, and at midpoint is about a 60 basis point drag in margin year-over-year.
Finally, the increase in free cash flow reflects the puts and takes, from the changes I mentioned and remains robust at a midpoint of $1.8 billion.
Operator, would you please open the line.

user
qtrly adjusted earnings per share of $3.45.

assistant