D. Barbour
Analyst · Baird
Thanks, Mike, and good morning, everyone. Thank you for joining us on today's call. We achieved a record $669 million of sales in the first quarter, 32% growth over last year. Growth was split fairly evenly, weighted a little bit more to favorable pricing than volume growth.
Demand remained strong at both ADS and in Infiltrator throughout our end markets and geographic footprint. In addition, international sales increased 82% this quarter with growth in our Canadian, Mexican and exports businesses.
Our backlog and pace of orders remain favorable as well as our ability to capture price in the market, giving us confidence in the updated sales targets we issued today.
We have issued several price increases since late last year to cover inflationary cost pressure, and we'll continue to use our leading market position in that respect as well as ADS and Infiltrator's scale position in material procurement and recycling operations to procure material at the best possible cost and availability.
Moving to profitability. Our adjusted EBITDA increased 4% on a dollar basis given -- again, driven by the favorable pricing and strong volume growth. The price increases we issued over the last 10 months largely covered the inflationary pressure on materials and diesel. There are additional headwinds related to driver availability, an increase in the use of common carrier and an increase in common carrier rates that we are working to offset.
We remain confident in our ability to identify and execute the right mitigation programs and expand our margins over time. Material prices started to rise in October 2020, increasing more significantly as a result of the winter storms that hit the Gulf region in February of 2021.
In the first quarter, our material cost per pound increased significantly compared to the prior year. Additionally, in the second quarter, we will experience the largest gap between historically high material prices this year and historically low material prices of last year.
The price increases we pushed into the market are largely covering material, and we continue to raise prices in line with these material increases as well as reprice quotes over 30 days old to ensure we're recovering the sequentially higher cost.
Material availability has improved since our last call. It comes at a price, but we are doing what it takes to give materials out to our facilities so we can support customer needs, including incurring additional transportation costs and shuffling production scheduling more than we have in the past.
We remain committed to meeting our customers' demand and have efforts underway to ensure we continue to do so. Across the market, attracting and retaining manufacturing labor and drivers is difficult right now. We've had to increase the pay rate in many locations to help mitigate this issue, both starting pay as well as raises for current employees. In addition, last year, we delayed all manufacturing merit increases until the second quarter due to the COVID-19 pandemic, making the first quarter year-over-year comparison more pronounced than usual.
Within transportation, there are 3 major factors driving additional costs. One, we have a shortage of available drivers for our fleet, requiring us to utilize more common carriers than normal to service our customers.
Number two, common carrier rates are up over 50% year-on-year. And number three, we're moving more material throughout the network to get it into the right locations so we can meet customer demand.
While 3 of our largest cost components, materials, labor and transportation, have a lot of moving parts, we're responding with the following programs. To address the labor issues within manufacturing, we are focused on simplifying the manufacturing process for new employees, including focusing production and decreasing SKUs, reducing changeovers and deploy centralized scheduling techniques.
We've also consolidated inventory of some key products to fewer locations for better visibility and order management, again, simplifying the task and providing better visibility.
Management time is focused on a handful of locations where we have the most issues, particularly with labor and capacity. We've created dedicated transportation lanes and are deploying route planning techniques to help with the transportation labor shortage. As well, we've expanded the use of 3PL partnerships for retail to an additional region which freed up ADS fleet capacity for trade deliveries.
More broadly, on labor, we have added recruiting process outsourcing partnerships for our manufactured and transportation labor hiring, which has improved both the applicant flow and the onboarding process. Where possible, we've increased pipe imports from our Mexican and Canadian operations to further supplement supply and availability in the U.S.
Finally, we are making capital investments to increase capacity with some having an impact in Q4 for Infiltrator and the ADS pipe manufacturing. We started up a pipe production line this month in the Midwest to increase capacity, and we've also made aggressive investments in the strong tech business to increase production capacity. We saw capital spending increasing year-over-year in the first quarter, and this will continue as we invest in the long-term potential of both businesses.
All that said, the momentum underpinning the core drivers of our business remains strong. Infiltrator maintained the high levels of profitability in the first quarter, despite similar challenges around materials, labor and transportation.
The international businesses also performed very well with double-digit revenue and EBITDA growth in each of those businesses. The domestic pipe business is large and complex, and while we are very proud of the sales volume and pricing power, there are work guidance, particularly with labor and transportation, which we'll have to grind through and continue to improve.
While some of these work items are inflationary and potentially transitory, others are operational that needs to be worked through systematically. And the areas where we started implementing programs using these techniques, namely the agriculture business, Canada and Florida, we've seen positive results over the years.
However, throughout our larger manufacturing network is our task now. The ADS legacy and Infiltrator businesses combined to have their best sales quarter in our history. The combination of the highest demand we've seen in our history across all regions simultaneously, in an environment with labor and driver shortages and rapid inflation.
This all came on us and our industry like very quickly in May and June. And given this environment, we expect our profitability going forward to look different quarter-to-quarter this year, more like the seasonality in fiscal 2018 when we made the majority of our profitability dollar growth in the back half of the year.
With that, I'll turn the call over to Scott Cottrill to further discuss our financial results.