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: We appreciate your patience while we work through some of the technical issues.
As you know, there's a new process and procedure for calling into these calls, and the vendor and the operator were working through that.
So, again, we appreciate you being patient during the delay.
A copy of the release has also been included in an 8-K submitted to the SEC.
Fiscal 2021 started off strong as demand and business activity in the first quarter remain stable at the top with some underlying variability by state and end market.
Organic sales grew 3%.
And recall that we communicated to you in May that customers bought approximately $20 million of product in the fourth quarter of fiscal 2020 due to pre-buying in our construction end markets and favorable weather conditions in our agricultural end market.
Absent this dynamic, first quarter organic sales would have increased 8% and non-residential would have been flat year-over-year.
Domestically, we had strong performance in key growth states like the Carolinas, Florida, the Southeast and Utah, and we were able to offset sales in states that reduced construction activity due to the COVID pandemic early in the quarter.
As a whole, we benefited from our national presence, as well as our geographic and end market exposure, including the increased exposure of the Infiltrator and ADS' focused homebuilder programs provide to the residential end market and our strong presence in the agricultural market.
We had another strong quarter in the domestic agriculture business, where sales grew 36%.
This growth was primarily driven by actions previously taken to increase our focus on performance in this end market, as well as positive underlying demand in this market and what was a strong spring selling season.
A lot of good work is being done in the sales and operations initiatives we defined as part of the renewed focus on agriculture at ADS, and the fall season is shaping up favorably.
International net sales decreased 9% in the quarter.
Sales in our Canada business did well, but it was not enough to offset weakness in Mexico in our exports business.
We have recently hired a new Senior Vice President of our International segment, Tom Waun.
Tom comes to ADS after a successful career at Emerson, and we are excited to have him as a member of our team.
Tom has decades-long experience in executive management, strategy and sales, and I look forward to working with Tom to improve the performance of our International segment.
Infiltrator once again exceeded revenue expectations with sales growth accelerating as we progressed through the first quarter.
Infiltrator sales increased across their product portfolio with a strong underlying demand in the residential and repair-remodel end markets.
Roy and his team believe, and I agree, that the favorable trends for single-family housing brought on by the pandemic are quite favorable for Infiltrator, so we are making additional capital and resource investments there.
As we get into the second quarter, demand looks very similar to what we experienced in the first quarter.
Our order book, project tracking, book-to-bill ratio and backlog are all positive, and we feel good about the first half of our fiscal 2021.
We expect the normal seasonal patterns to apply to the business, which only sharpens our focus for this first half of the year.
As mentioned previously, our national presence, distribution model and end market exposure enable us to capitalize on growth and activity across the US.
As you can see on the chart on the screen, our residential end market exposure has increased to 38% of domestic sales, our second largest domestic end market behind non-residential.
We view this as favorable, given current market trends and the uncertainty in the non-residential market.
The residential market should benefit from single-family housing undersupply and potential future suburban trends as people look to spread out in the aftermath of the COVID pandemic.
This dynamic should also benefit horizontal, non-residential and infrastructure development as developers look to support the increase in single-family homes and communities.
I think in the first quarter with the residential portions of ADS and, of course, Infiltrator growing to double digits, the success of our renewed focus on the agriculture market and the uptick in the sales to the retail segment, driven by the DIY and stay-at-home project activity, demonstrated to us the power of this end market diversity and we've initiated several programs to increase success across these markets so we can be prepared for changes in demand across our business.
From a profitability standpoint, we achieved record adjusted EBITDA in the first quarter.
Organic adjusted EBITDA margin increased 830 basis points, driven by favorable material costs, lower manufacturing and transportation costs driven by our operational initiatives, contributions from the proactive cost mitigation steps announced in March and leverage from the growth in pipe and allied products.
Infiltrator also has record profitability in the quarter due to favorable material costs, the contributions from the synergy programs and continued execution of their proven business model.
The synergy programs are right on track to achieve the run rate synergies we've previously communicated.
Similar to my comment earlier on the second quarter revenue, the second quarter profitability trends continue in much the same way as the first quarter at both ADS and Infiltrator.
We are making good progress on our operational improvement initiatives within our manufacturing and distribution network.
Material pricing remains favorable to the prior year, though the comparison will become more difficult as the year progresses.
We will continue to watch our spending very closely as we deal with many of the same issues that other companies are dealing with.
Reopening is presenting challenges, including recruiting and retaining production workers, absenteeism, and all of these challenges we have to deal with on a daily basis.
We've had roughly 80% of the salaried workforce, including sales, pretty much working from home since late March.
So there are a lot of issues you would expect that we're dealing with daily.
We have made adjustments and proven to ourselves that we know how to run the business in these conditions, and that's what we'll to focus on as we manage through this period of unique circumstances.
There's no doubt that uncertainties exist for future demand.
We will be focused on disciplined execution and doing the basics well as we move forward through fiscal 2021 and build on the strong start at both ADS and Infiltrator.
On Slide 6, we present our first quarter fiscal 2021 financial performance.
Net sales increased 23%, with 3% organic growth plus the contribution of Infiltrator.
Within ADS, domestic sales increased 4%, driven by sales growth in both the agriculture and construction end markets.
Importantly, sales increased 4% in both pipes and allied products.
Construction sales accelerated at the end of the quarter as states with more stringent restrictions for the pandemic began to open back up.
From a profitability standpoint, our adjusted EBITDA increased $79 million, or 99% compared to the prior year.
Our organic adjusted EBITDA increased $38 million, with strong performance from our sales, operations, procurement and distribution teams.
ADS is very well positioned to capitalize on the current stability in our end markets, as well as lower input costs, given our market-leading position, breadth of products and services, geographic and end market diversity, as well as our national relationships.
These attributes or modes make us the premier partner and leader in the industry and led to the margin expansion and financial performance in the quarter.
Infiltrator contributed an additional $42 million to adjusted EBITDA and has many of the same benefits as ADS in this market environment.
Infiltrator achieved a record adjusted EBITDA margin this quarter and is in a very good position to grow as a result of the underlying demand in the residential market, as well as their material conversion strategy.
Moving to free cash flow on Slide 7.
We more than doubled our free cash flow in the quarter, increasing from $53 million in the first quarter of fiscal 2020 to $124 million in fiscal 2021.
The very strong free cash flow results were driven by the strong sales growth and profitability we achieved in the quarter, as well as execution on our working capital initiatives.
Our working capital as a percent of sales decreased to about 21% as compared to about 25% last year.
Finally, on Slide 8, we present our current capital structure.
Our trailing 12-month pro forma leverage ratio is now 1.9 times below our target range of 2 times to 3 times levered we've previously communicated and well ahead of our original target to achieve a leverage ratio of less than 3 times by the end of this calendar year.
This performance was achieved as a result of our working capital initiatives, as well as the strong profitability performance we demonstrated both in fiscal 2020, as well as in this quarter.
We ended the quarter in a very favorable liquidity position, with $235 million in cash on June 30, 2020 and $289 million available under our revolving credit facility, bringing our total liquidity to $524 million.
It is also important to note that we have no significant debt maturities until 2026.
Further, we paid down the remaining $50 million balance on our revolving credit facility this past Friday, bringing that balance to zero as of today.
Our capital deployment priorities remain to invest in our business with a focus on safety, capacity expansion, productivity and efficiency improvements, as well as our innovation initiatives.
In addition, we will continue to assess bolt-on acquisition opportunities through our discipline process, staying close to our core and focusing on adding products to our water management solutions package.
Lastly, due to the uncertain market environment, we are not providing guidance on the call today.
Operator, please open the lines.

user
not issuing financial guidance at this time.

assistant