Good morning to you all, and thanks for joining us on our call following the release of our trading statement a few minutes ago. I have with me Jonathan Timmis, our CFO, and Denis Moreau, our VP of Investor Relations. There are essentially three takeaways in our call today. First, we've made strong progress in H2. In the July-October period, we've delivered a revenue growth of 6.7% at constant currency, driven by robust like-for-like revenue growth and our two recent acquisitions. We've also benefited from positive momentum in margin and cash. Second, we are on track to deliver our full year targets of robust like-for-like revenue growth, year-on-year margin progression, and a strong free cash flow. Third, COVID-19 has been much more than a tragic pandemic for the entire world. COVID-19 has made the case for total quality assurance stronger.
Our clients have realized that they will need to increase their investment in quality assurance to operate with higher quality, safety, and sustainability standards. Post-COVID, we expect the global quality assurance industry to grow faster. I would like to start our call today with a few comments on what's happening in the supply chains of our clients. COVID-19 will be remembered as the greatest dislocation of the global supply chain since the 1970s, creating significant challenges across the world. This includes the lack of PPE and medical devices during the phase one of the pandemic, shortage of components and raw materials in multiple industries in multiple markets, containers not being available for the global trade rebound, resulting in empty shelves in supermarkets and out-of-stock notices in e-commerce across many product categories. Of course, shortage of labor in many sectors of the economy, putting inflationary pressure on wages.
Finally, lack of synchronization between demand and supply in the world's energy market, creating a shortage of electricity in several countries and putting inflationary pressure on energy costs. Essentially, the disruption we are seeing in the global supply chain of our clients is a compounding effect of three factors. A rapid fall, of course, of global demand in Q2 2020, triggering cost reductions in major sectors, resulting in low stock levels and a smaller workforce. A rapid rebound of the global demand in Q4 2020 and H1 2021 for many product categories running well ahead of lowered expectations. A lack of business intelligence inside corporations to read the global trade rebound early and start ordering and hiring on time.
At Intertek, we are supporting, on a daily basis, over 400,000 customers as they try to synchronize their sourcing, production, and logistics activities to get their supply chains back to normal and serve their clients. The supply chain disruptions within the ecosystems of our clients is highly complex. Although everybody is working hard, it will take time before the global supply chain is back to normal. There is a major learning for our clients from these significant global supply chain disruptions. They've been operating with substantial intrinsic risks in their supply chains without the right data. This is why we expect our clients to increase their investments in their supply chain in three areas. Safer supply chains is their number one investment area priority. COVID-19 is indeed proving a catalyst for many corporations to improve the resilience of their supply chains.
We expect major corrective actions, and these will include better data on what's happening in all parts of the supply chain, tighter risk management with razor-sharp business continuity planning, a more diversified portfolio of tier one, two, and three suppliers, a more diversified portfolio of factories, including onshoring to both enhance supply chain resilience and reduce the carbon footprint of their operations, and investments in processes, technology, and training to step up their supply chain capabilities. We're also seeing our clients realize that in addition to their supply chain challenges, they need to invest more in product and service innovation to meet the changing needs of their consumers. As you would expect during a major global crisis like COVID-19, consumers' expectations are changing given their desire to live in a much better world. Building back better is on everybody's minds.
Indeed, corporations need to step up their game in quality, safety, sustainability, convenience, and value formulae to enhance their products and services. The third major area of investments inside corporations is, of course, sustainability. The sprint to net zero emissions is real, and corporations are having to reinvent the way they reduce their carbon footprint across the entirety of their operations and the way they communicate the progress they are making on net zero with carbon emission claims independently verified. In summary, our clients are seeing a strong yet uneven global recovery with two major challenges. First, they need to resolve immediately the disruptions in their global supply chains to meet the needs of their clients. Second, they need to invest in safer and more resilient supply chains, innovation to make their product and services better, and of course, sustainability.
These additional investments of our clients in their quality assurance activities will provide Intertek with additional growth opportunities. I would like now to discuss our performance in each of our business lines over the last four months, starting with Products. Notwithstanding some supply chain issues, our Softlines clients continue to benefit from the reopening of the global economy, with the demand for online shopping and sustainable products being the strongest. This has enabled us to deliver mid-single-digit like-for-like revenue growth. In addition to these trends, our Hardlines clients are also benefiting from increased consumer spending on home products and furniture. Like-for-like revenue growth was high single digit in Hardlines. In the electrical and connected world, our clients are seeing increased demand for high efficiency in electrical products as well as for 5G connected devices.
We delivered a mid-single-digit like-for-like revenue growth. Companies continue to invest in risk assurance as well as sustainability, enabling us to report high single-digit like-for-like revenue growth in the period for our Business Assurance business. Within North America, the demand for greener building remained solid, while large construction projects were still being built last year, we delivered a stable like-for-like revenue. As expected, our TT clients started to resume R&D investments in greener powertrains, and we delivered a high single-digit like-for-like revenue growth. Consumer demands for safety and healthier food remained strong, enabling us to produce high single-digit like-for-like revenue growth. Our chemical and pharma business reported double-digit like-for-like revenue growth. Our clients continue to invest in regulatory assurance, and our pharma clients increased their R&D testing. Moving now to trade, where the expected improvement in global mobility has been beneficial for Caleb Brett, which delivered a mid-single-digit like-for-like revenue growth.
The shortage of containers continued to impact the trade flows in the Middle East and Africa. Our GTS business delivered stable like-for-like revenue. The demand for agri products remained strong, driven by the strong growth in the global food industry, and we delivered double-digit like-for-like revenue growth within this business line. Our clients are starting to benefit from the global economic recovery within the resource sector. We saw an acceleration of demand for minerals, enabling us to report double-digit like-for-like revenue growth. Within the energy sector, companies increased maintenance activities in their operations, leading to mid-single-digit like-for-like revenue growth within OpEx inspection. As expected, our clients are starting to increase their investments in exploration and production, enabling us to deliver a stable like-for-like revenue in CapEx inspection.
Having discussed what's happening in the world of our clients and how we've performed within each of our business lines, let me summarize the highlights of our performance at the group level in the period. Revenue growth of 6.7% at constant currency, with revenue accelerating during the period July, August, 4.8%, September, October, 8.5%. We delivered like-for-like revenue growth of 5%, notwithstanding the loss of 1 working day. Our trading days adjusted like-for-like revenue growth was 6.2%. All divisions delivered like-for-like revenue growth, products 5.5%, trade 3.7%, resource 4.7%. Our SAI and GLA acquisitions are performing well in revenue margin and cash. Our disciplined cost and productivity management has enabled us to deliver an improved margin versus H1.
Our disciplined cash performance management continues to drive a strong cash performance. Based on a strong performance we delivered in H1 in revenue, margin, cash and ROIC, and given the July-October trading performance we have just discussed, we are on track to deliver our full-year 2021 targets. We continue to expect that the group will deliver robust like-for-like revenue growth at constant currency, notwithstanding the lockdown restrictions in a few markets and the supply chain challenges that our clients are facing. We continue to expect the product divisions will deliver robust like-for-like revenue growth, with trade and resources both expected to report good like-for-like revenue growth. We continue to expect margin progression year-on-year and a strong free cash flow performance. Our guidance regarding net finance cost, tax rate and minority interest remains unchanged.
Regarding currency, we continue to expect that the average Forex rate applied for the full-year result would reduce our revenue and earnings by circa 500 basis points. Before any material change in Forex rates or M&A, we continue to expect our financial net debt to be between GBP 835 million and GBP 885 million at year-end. Looking beyond 2021, we expect the industry growth drivers to be stronger post-COVID-19. The global crisis that we are emerging from has demonstrated there were major risks in the world that were not properly identified and mitigated pre-COVID-19. Moving forward, all stakeholders in society expect governments and corporations to build back a better world with sharper focus on end-to-end quality assurance. The supply chain disruptions being experienced by corporations across multiple industries has made the need for comprehensive risk-based quality, safety and sustainability assurance more critical than ever.
We are well positioned to benefit from the increased investments in quality assurance from our clients. We are the global leader in risk-based quality assurance with the depth and breadth of our unique ATIC solutions. Given our high margin, capital light, carbon light and strongly cash generative earnings model, we'll continue to deliver sustained value for all stakeholders moving forward. In summary, we've made strong progress in H2. We are on track to deliver our full-year targets. Post-COVID, we expect strong investments in quality assurance from our clients.