Hello, I'm Andy Walters, founder of Quartix Technologies PLC. I returned to the company in late 2023 as Executive Chairman. This presentation covers our full-year results for 2024. It's available to download together with our annual report on our investor site. Our customers are typically SME companies with mobile workers who travel to customers' sites for their work. Through tracking their vans, we provide them with business and operational information on a subscription basis using web and mobile-based applications. This has been the basis of our business right from the start. The most significant financial benefit to them of using our service is that of increased business capacity. Our base has grown strongly since 2001, and today we have over 300,000 vehicles under subscription. We started out in the U.K but we've added five other target markets since, and our systems are entirely based on in-house owned and developed IP.
This chart shows the equivalent growth in our customer base, also split by market. Our customers are typically in sectors such as construction and building, service and maintenance, land and ground works, and the public sector. Sixty percent of our customers are outside the U.K, and these markets are growing at a rapid rate for us. Despite the overall progress, the customer bases in the U.K and U.S.A. were slowing as the company lost focus towards the end of 2022, and this was the principal reason for my return at the end of 2023, although other factors emerged following my return. We have put these issues behind us, as you'll see from these results. These three green lines show progress in customer acquisition between 2020 and 2022, and the loss of momentum is evident in the gradient by the middle of 2022.
This resulted in weak performance in 2023, which we've successfully turned around by the middle of 2024, in fact, reversing the decline in the U.K and U.S. customer bases which had developed. We clearly established by the end of the year a period of record customer acquisition , which has continued into 2025. We're now adding more than 700 new customers per month. The value of our subscription base, Annualised Recurring Revenue, is the key indicator of our future revenues and profit. We increased ARR by a record GBP 3.5 million in 2024, which was 68% ahead of the growth achieved in 2023. Growth in ARR needs to be achieved cost-effectively, and we've made great improvements here also by reducing and redirecting overhead spend. Another important indicator for us is our revenue retention, or Net Revenue Retention.
This measures how much we retain in value terms of our customer base each year. At the end of 2024, we had retained 95.7% of the value of our starting customer base for the year. This was a 2.7 percentage point increase in that retention over the performance in 2023. That gives us a base on which to grow from new customer acquisition , and this was also significantly ahead of the prior year, as the previous slide showed, generating GBP 4.7 million worth of new business, bringing ARR at year-end to GBP 32.2 million, or 12.2% ahead of growth overall. To put that improvement in context, this slide shows the company's progress from 2020 to 2022 in three green lines detailing cumulative growth in ARR through each of those years. Following that loss of focus I mentioned, overall performance slipped, as can be seen in the red line in 2023.
The company had attempted to diversify through development of some new services and the acquisition of a loss-making business called Konetik in Germany. Immediately following my return at the end of 2023, we started liquidation proceedings for Konetik and refocused on our core telematics business. The results can be seen in the orange line. The significant jump at the start of the year came from a revision to pricing to help compensate for the increases in overheads and input costs, which have grown significantly in the previous two years. Towards the end of the year, the gathering momentum in new business can be seen in the steeper gradient of the line. This graph splits that improvement by market. The top left shows ARR by country, and the bottom right shows the contribution made to growth in millions of GBP by each country.
This second graph gives a better indication of the potential of each market. Growth in the U.K trebled. France made the strongest contribution. The U.S.A. was turned around from a deficit in 2023 to a gain of GBP 0.2 million, largely in the final few months of the year. Italy, Spain, and Germany each showed excellent contributions, with particularly notable progress in Italy. I am going to briefly cover the financial results before going into more detail in a couple of areas. Revenue increased by 8.4% to GBP 32.4 million. It was actually slightly higher than on a constant currency basis, but 8.4% in actual. Operating profit, with last year's result adjusted to remove the exceptional costs taken that I have referred to, increased by 25% to GBP 6.3 million, and the net result produced earnings per share of 9.85p versus a loss last year.
Now, free cash flow remains low relative to profit, but I've got more detail on that later on. To provide more detailed financial results, we report our performance in two segments: Total Fleet and the Konetik subsidiary. The Total Fleet segment has then been subdivided into two further categories you can see here. This has been done to give clarity as to the level of upfront investment we make in acquiring new customers, as well as the associated impact on recurring revenue. The two subcategories are customer acquisition . This is the revenue associated with new business that we win during the year, and this is principally our sales and marketing investment and installation of new systems, together with a small proportion of overall service costs that are shown in the cost line.
Fleet Telematics Services , this is the recurring revenue associated with the group's active subscription base and the cost of servicing it. The costs in this subcategory include the cost of installing additional units for existing customers and any associated sales and support costs. These two elements, together with the central fleet costs, make up the Total Fleet segment, and this analysis shows the investment being made in developing the business alongside the profit being derived from the existing base. The balance between the two is entirely within our control, and in 2024, we increased sales and marketing investment by 12% to GBP 7.1 million. The final point on this slide is that the net cost of Konetik to the P&L account in the year was about GBP 350,000, reducing operating profit from GBP 6.8 million to just under GBP 6.5 million, and we've provided for all future anticipated costs from Konetik.
We further split out our financial results to show the transition in overheads throughout the year. Administrative expenses reduced by 12% from the first half to the second half, and half of these savings were reinvested in sales and marketing, resulting in an 11% increase in investment. This included recruiting new sales agents to support the US market and increasing marketing expenditures to drive lead generation. Net of these improvements, total overheads decreased by 9% in the second half. In addition, we achieved savings in manufacturing costs, which will also reduce the future cost of the French upgrade program, and revenue grew in the second half thanks to strong ARR growth in H1. In total, operating profit was GBP 1 million higher in the second half than in the first.
Before moving on to product development, I'll just briefly mention cash flow again, which remained low by our normal standards. This diagram shows the reported free cash flow on the left, and then the cash costs of both the Konetik acquisition and liquidation, followed by the cash cost of the French upgrade program, demonstrating the underlying cash flow before these items would have been around GBP 4.5 million. Additional cash was invested in building stocks for the upgrade program, which started in the second quarter of last year, but we've not estimated or shown those. We made good progress in product development, particularly in hardware. Development of our latest telematics system, the TCSV17, was initiated and released to production during the year in just under 12 months. The development marked the most significant revision of both hardware and firmware design for at least a decade.
The design objectives were focused principally on cost reduction, but some significant advances have also been made in performance. The cost saving achieved is approximately GBP 8 per unit, and the TCSV17 will account for 7,000 units per month, at least, of usage in 2025 from July onwards, after we've used up stocks of the existing product. Initial versions of revised web-based and mobile tracking applications were developed and released during the year. The mobile app was completed in January this year, and development and rollout of the new web-based application will be accelerated in 2025. All of our investment in research and development was fully expensed in the year. None of it's capitalized.
Now, although there's been significant change at PLC board level since our return, I did want to emphasize in this slide the leadership that the company has in its executive management team, where each member has at least seven years' service to the company. Through the changes we've made at the PLC board level, we've been able to enable the management team to focus on our core business, with the results of the turnaround over the past year now clearly in evidence. There's a lot to summarize in this final slide, and I'll try and keep it brief. We've put the issues of 2023 behind us through the liquidation of Konetik and the implementation of the French upgrade program. We reduced overheads whilst increasing investment in sales and marketing.
We've adjusted pricing to help compensate for inflationary pressures felt in 2022 and 2023, and we're going to continue to do so with a slight increase in that indexation this year. The net result has been the achievement of record growth in ARR, combined with a 25% increase in pre-tax profit. The group has started 2025 well with strong order intake, revenue, and new customer acquisition . New monthly subscriptions of over 8,000 vehicles in January marked a significant new monthly record for the group, and the prospects for continued strong growth in ARR are good, and the group continues to control its overheads well. The board believes that there's significant scope for continued growth in our existing six markets, and this will remain the focus for 2025 and 2026.
The board and I will strive to maximize efficiency and improve the group's growth potential this year and have further upgraded our outlook on profit for 2025. Thank you very much for listening.