Udit Batra
President and Chief Executive Officer at Waters
Thank you, Caspar and good morning everyone. I would like to begin today's call by expressing my gratitude to all my colleagues. 2023 was another transformative year for Waters. Throughout the year, our teams kept an unwavering focus on customers, launched innovative new products, and delivered strong business performance, all during highly eventful times with dynamic market conditions. As 2022 ended, the results of our transformation clearly showed on the top line. Having delivered several years of very strong, above-average sales growth.
Since then in 2023, we have demonstrated our ability to manage exceptionally well through a downturn while continuing to make investments for growth. In 2023, we also initiated the next phase of our transformation with the acquisition of Wyatt. This brings with it a new vector for value creation to our shareholders through M&A, and we're off to a great start. As an added benefit, it has accelerated our journey into high growth adjacent markets where we made continued progress with our organic investments over the course of the year.
We launched new and innovative products in 2023, including our Alliance iS next generation LC platform. We expanded our Xevo TQ mass spec into clinical applications and developed size exclusion columns for viral vectors that pair with Wyatt MALS instruments. We even had our first light scattering launch as a combined company with DataStar. Finally, we were recognized as one of the world's most sustainable companies, achieving a variety of ESG awards. This includes our top five ranking on Barron's most sustainables Companies list, which scores over 1000 publicly traded companies based on 230 ESG performance indicators.
We are very proud of what we've achieved at Waters in 2023. Today, as I share our fourth quarter and full year results, I have three key messages. First, we've continued to execute well. Second, our transformation is contributing to our results and third, we are well-positioned for future long term growth. Turning now to our results. In the fourth quarter, sales declined 4.5% as reported, which was in line with our expectations. Our non-GAAP earnings per fully diluted share landed at the high end of our guidance at $3.62, driven by strong margin performance. On a GAAP basis, EPS was $3.65.
For the full year, sales declined 0.5% as reported and 2% in organic constant currency. Even with a constrained capex environment, all our regions outside of China grew in 2023 in organic constant currency terms. As expected, Wyatt successfully delivered on target M&A contribution of 2.5% to sales and with a strong EPS result in Q4 non GAAP earnings per fully diluted share came in at $11.75, which reflects underlying growth of approximately 2% before FX headwinds of 3% and 1% dilution from the Wyatt acquisition.
I will now describe our sales results in more detail. The spending environment for instruments remained challenging into year end. However, Q4 revenue increased versus Q3 levels in all our geographies, even China, as we continued to execute well in tough macro conditions. Reported sales were 108 million higher in the fourth quarter than the third quarter. This reflects a 15% ramp that was consistent with our guidance for a muted year-end budget flush. For the full year, our organic constant currency sales grew 3% year over year, excluding China.
As I mentioned earlier, the Americas, Europe, and Asia, excluding China, all grew in 2023. This took a lot of effort from our sales team, who did a fantastic job capitalizing on the available opportunities in the market with our competitive portfolio. As a result, on a four year stack basis, our ex-China growth remains at a healthy high single digits. A key challenge in 2023 was the abrupt turn we saw in China where conditions deteriorated as the year progressed. This was particularly the case in the pharma market where our revenues are most heavily weighted.
For the full year, China sales declined more than 20% overall, which was a 5% headwind to our total growth. This brings us now to our margin performance. We believe that the best reflection of good operational execution is effective margin management when things slow down. During 2023, we saw volume and FX headwinds while inflationary pressure continued. We responded with stronger pricing and added further discipline to our operational objectives. We redoubled our productivity efforts, including the opening of our global capability center in Bangalore, India, and we undertook proactive cost alignment as the slowdown began to emerge.
This resilience, focus, and commitment allowed us to deliver excellent operational results in our P&L. Our full year gross margin was 59.6%, which is 160 basis points better than the previous year. Our full year adjusted operating margin was 30.9%, which is 70 basis points of expansion. Now let me share our progress with the acquisition of Wyatt Technology. The strong start to lead sharing between Wyatt and Waters, allowed us to offset a slowdown in biotech spending, resulting in an on target M&A contribution of 2.5% to our full year sales. I will now give some detail on how our revitalized portfolio and alignment with higher growth segments are contributing to growth as part of our transformation.
Our strong results in 2023 were supported by our innovative portfolio which helped drive customer spending. Our new products are gaining good traction in the market including TQ Absolute, Alliance iS, and MaxPeak Premier columns, as well as several of our high-res mass spec instruments such as Cyclic G3 and MRT. From an adoption perspective, this puts us in an excellent position when instrument budgets begin to normalize. Turning now to our adjacencies, we have continued to invest and expand into adjacent high growth markets where our business model of solving problems in downstream regulated applications can be deployed.
For bio-separations and bioanalytical characterizations we've made organic investments, launched new products, and deployed capital to M&A. Large molecule applications are now 35% of our pharma revenues and expected to trend higher, up from around 20% just few years ago. For diagnostics, we have invested in our clinical business and added work flows for specialty applications of mass spec. This has transformed related revenue growth from that of low to mid single digits to double digits in the past several years. Finally, our focus on batteries is paying dividends where very strong growth has remained throughout the year. Revenues from battery applications are now at over ten times 2019 revenue levels and our TA business is increasing aligned with less cyclical, faster growing applications.
Each of these exciting growth areas is delivering incremental revenue to the company. Now, I will share some facts supporting the long term outlook for above average growth and provide our 2024 guidance. Since 2010, Waters has grown on average 6% in organic constant currency terms. For instruments, while the standard deviation is high, long term average growth has been 5%. For recurring revenues, the standard deviation is much lower and the average growth is 7%. As we look ahead, several vectors make us confident that this growth could be even higher. The first is even faster volume growth in segments that we serve, driven by global prescription drug sales and environmental regulations.
Second is increased use of analytical instruments for characterizing large molecules and novel modalities and third is above historic pricing where we expect to sustain 100 basis point long term tailwind in incremental growth. Let's take each of these growth vectors in turn. There are at least two key drivers of testing volume acceleration. The first is related to the adoption of GLP-1 drugs where Waters instruments and columns are specified into in process testing and QA/QC testing at the two leading manufacturers. We expect our position to contribute an average additional revenue growth of 30 basis points per year between now and 2030.
The second is PFAS testing, where we've been gaining share in a rapidly expanding market, in part driven by the sensitivity and compact size of our Xevo TQ Absolute mass spec. We expect PFAS testing to contribute an additional 30 basis points to our revenue growth for the foreseeable future. Finally, Wyatt Light scattering is a high growth business serving attractive large molecule applications. We expect it to contribute 40 basis points of core growth accretion to our business on an annualized basis. It also accelerates our ability to solve customer challenges in formulation development, bioanalytical characterization, and QA/QC testing, which has positive repercussions for our waters business as we increasingly tie our columns, LC, and mass spec into these workflows.
I will now cover our 2024 full year guidance. We expect customer spending caution to continue in the first quarter of the year with slow budget releases for downstream instrumentation. We then expect to see a gradual improvement for the remainder of the year as budgets open up, market conditions improve, and as prior year comparisons become easier. We expect weakness in China to continue, particularly in the first half of the year, which also plays into the growth phasing of our guide. With this initial outlook for 2024, we expect full year organic constant currency sales growth to be between negative 0.5% to positive 1.5%.
We expect continued strong operational performance to build leverage in our P&L with 20 to 30 basis points of further operating margin expansion while still reinvesting for growth and we expect adjusted EPS growth of 0% to 3% in the range of $11.75 to $12.05. Now I will pass the call over to Amol to continue covering our fourth quarter financial results in more detail and give additional commentary on our guidance for 2024. Amol?