Welcome. I'm Simon Henry, CEO, DGL Group. I'm here to take you through the FY 2023 full year results presentation. This presentation is also available on our website under the Investor link. Turning to slide. DGL has had a solid FY 2023. Sales revenue rising 26% to AUD 466 million. Underlying EBITDA is up 27% to AUD 64.1 million. We have increased our employees to over 800, our active customers to over 4,200. We operate from over 70 sites across Australia and New Zealand, and have significantly increased our transport capabilities. Turning to slide 4. DGL Group continues to perform strongly. Sales revenue up 26%, gross profit up 25%, underlying EBITDA up 27%, and underlying EBIT up 25%. Turning to slide 5, operational highlights.
DGL Group continues to expand its scale and its capabilities. This expand as it expands the products and services that we can offer, expands the geographies that we cover, and we're able to bring all of our segments together and achieve significant cross-selling between the segments and further increase our sales to the existing customers and attract new customers. We're extracting ongoing efficiencies and improvements by integrating our businesses and centralizing key services. Slide 6. DGL continues to grow. Revenue in FY 2023 increased as a result of increased sales volumes to existing customers, price increases to reflect higher input costs, and the acquisitions and increased cross-sell and the increased fleet trucks, tankers, and trailers. Revenue growth flowed through to underlying EBITDA, but at the same time, partially offset by inflationary pressures on employee benefit expenses.
FY 2023, net profit after tax decreased on a prior corresponding period, primarily as a result of increased financing costs from higher interest rates and increased borrowings, and a prior period tax adjustment and more conservative treatment of available tax loss utilization in New Zealand. Turning to Slide 7, increased capabilities and scale. Since FY 2021, staff numbers have increased 69%, trucks and trailers and tankers have increased 166%, and sites that we operate have increased by 58%. Turning to Slide 8, performance. A 26% increase in sales revenue in line with our June 2023 guidance. Able to push through price increases. Cost of sales increases are in line with revenue, including higher raw material prices.
Higher employee benefits expenses were integrated, and the integration of 270 acquired employees. Underlying EBITDA was up 27%, in line with revised guidance provided in June 2023. Second half of FY 2023, we encountered a significant shortage in lead-acid batteries, particularly in the final quarter of FY 2023, and also experienced uneven ordering patterns from key customers. We have a higher effect of FY 2023 tax rate of 33%, due to a more conservative treatment of available tax losses, tax loss utilization in New Zealand and a prior period tax adjustment. Turning to Slide 9, segment revenue. Chemical Manufacturing, up 126%, or 126% compounded annual growth in revenue since FY 2021. Strong demand for our increasing range of products.
Logistics, 59%, compounded annual growth rate since FY 2021, experiencing a very high rate of utilization of our warehousing facilities across Australia and New Zealand, and acquired 4 businesses in FY 2023, which contributed AUD 29.3 million to the segment. Environmental Solutions segment, 32% compounded annual growth in revenue since FY 2021. FY 2023 was a challenging year for our recycling business, with the shortage of lead-acid batteries, but offset by strong demand for our water treatment services, plus the contribution there from 4 acquisitions, contributing AUD 28.5 million in revenue to the segment. Moving on to Slide 10, the balance sheet. Strong and conservative balance sheet, providing us with the flexibility and headroom to support further growth and to meet customer demand in FY 2024. Net assets increased to AUD 336 million.
Property, plant, and equipment increased by 27.6 million, and net debt running at around AUD 91.1 million at 30th of June, which is about 1.4 times net debt to EBITDA. Inventory days are down from 76 to 46. Slide 11, cash flows. Robust operating cash flows of AUD 59.3 million and a very impressive cash conversion there of 118%. No dividend cas paid in FY 2023. Our dividend policy remains unchanged, with all earnings being reinvested to support growth. Slide 12. DGL has performed strongly in the face of price volatility and inflationary pressure. Well-capitalized, we have a diverse range of customers, and we're exposed to growth industries and are located in key geographies. We have strong relationships with raw material providers and end markets.
We continue to provide essential services to key industries and consistently in demand with our the growing customer base. Seeing robust demand from a broad customer base in our Chemical Manufacturing division, ongoing supply chain disruption, and customers looking for to be partnered with reliable vendors. Logistics, once again, we're seeing fewer players carrying out chemical logistics and a record high utilization of our warehouses. Environmental segment there, increasing demand for our water treatment services, increasing demand for our chemical dosing requirements into mining, and working in a highly regulated environment is driving growth. Moving on to Slide 13. FY 2023 achievements continued to cross-sell between our market between our segments. Acquired new businesses that enable us to provide more material, more products, more services, and cover more geographies.
We are extracting better value out of our assets across the group through having these segments work closer together. We have invested in capital and new projects. We've expanded our production capacity in Victoria. We've acquired a number of new sites to meet growing demand for chemical formulation and production. We will continue to buy strategic companies. We carried out 11 acquisitions in FY 23. These acquisitions add skilled employees, customers, a wider range of services and products, and cover geographies that we mightn't have covered previously. The acquisitions that we've made since IPO in 2021 are well on their way to being fully integrated into the group. Onto Slide 14.
Our planned activities for FY 2024 are the ongoing integration of our acquired businesses, a central focus on organic growth opportunities, using our wide range of assets and our customers and capabilities to further increase our sales. To further develop up our procurement department to reduce the cost of raw materials through bulk buying. The expansion of our DGL's formulation and transport offerings. We've commissioned a new industrial battery breaker in Victoria, which will, we hope, be a significant contributor to our environmental division. We have a new liquid waste treatment plant coming on stream in New South Wales. We have expanded our chemical production capacity across Australia and New Zealand, and this will be further enhanced throughout FY 2024.
We are implementing a new ERP and payroll system to automate our shared services across the group, and these will be rolled out through FY 2024. Continue to acquire well-priced and strategic companies when they come along, and obviously with the focus of these companies, just to fill out our service offering and bringing new customers into the group. Slide 15, senior management team. All experienced and working well, and looking forward to the future. ESG, in the process of appointing a senior full-time manager to further enhance our and develop out our ESG element of the business. Health and safety and environment. Pleased to be able to report there were no health and safety or environmental events that came about in FY 2023 of any significance. A remarkable achievement.
We are a chemical company, so operating safely is key to everything that we do. We certainly hope to continue this good record moving in through our FY 2024. Summary and outlook, slide 18. We are continuing to experience unprecedented demand for our products and services, and we certainly have the opportunity to sell more products and services, particularly along the East Coast of Australia. Our challenge will be to add in the additional capacity needed to meet this demand. Our priorities are to increase sales whilst being measured with new capital commitment and extracting greater value from our existing asset base and infrastructure, continue to deliver on our pipeline of organic growth investment. We will maintain a selective approach to assessing and selecting new potential strategic acquisitions.
We're focused on the ongoing centralization of services and support functions to increase return and drive efficiencies across the group. The outlook, DGL has experienced a solid start, a solid trading start to FY 2024, giving the Board confidence that despite ongoing volatility and uncertainty, the company's strong growth trajectory will continue throughout FY 2024. The company will remain focused over the next three or four years on our current markets in Australia and New Zealand to execute its long growth runway before looking further afield. That's all. I thank you very much for your time.