GROSS TONNAGE SHIFT

Gross tonnage (gt) is arguably the most misunderstood but commonly used term in the yachting industry. The definition bears repetition. Gross tonnage is a measurement used in the maritime industry to indicate the overall internal volume of a ship. It’s a standardised measure that includes the entire enclosed space within a vessel, including cargo holds, engine rooms, crew quarters and any other enclosed spaces.

Gross tonnage is calculated in accordance with international regulations set by the International Maritime Organ-ization (IMO). The formula for calculating gross tonnage considers the volume of the ship’s enclosed spaces and is used for various purposes, including determining registration fees, port dues and safety regulations.

It’s important to note that gross tonnage is distinct from a ship’s displacement, which refers to the weight of water displaced by the ship’s hull and is a measure of the ship’s actual physical size and buoyancy in water.

While not directly representative of the ship’s mass, it does give a great yardstick as to design trends and the amount of usable space for an owner, and crucially, yachts above a certain gross tonnage threshold may be subject to stricter regulatory requirements for commercial operation.

To encompass the important 500gt and 3,000gt thresholds, this analysis uses slightly different size brackets, 4560 metres to capture the 500gt mark and 80-100 metres to capture the 3,000gt.

There is an inbuilt flexibility in these Gross tonnage calculations, with some designers and shipyards using the full range of the regulations to keep a vessel below a certain regulatory threshold. When the fleet’s gross tonnage is plotted on a scatter plot, it’s fairly obvious where these demarcations occur. This is starkest in the 45-60-metre-plus sector. The logjam of vessels at 499gt is clear to see. Understandably, there are very few yachts between 500gt and 600gt. A sim-plistic way to view this is that in the design process, if a yacht is going to be over that threshold, it may as well maximise its volume and usable space.

Even segmented into a narrow bracket of 45-60m, the variance in gross tonnage is drastic. Outliers of note here, and to give context, the lowest gross tonnage motoryacht is the 2001 Turquoise Yachts Arriva at 48 metres and 229gt. The most voluminous launched yacht in this size bracket is the 2008 Lürssen Vive la Vie, at 59m and 1,277gt. This will be surpassed in 2024 by a 58-metre RMX Marine project that comes in at a colossal 1,365gt.

The 80-100m scatter plot displays the same trend around the 3,000gt mark, although less pronounced due to the lower number of yachts in this fleet. The grouping of yachts at 2,999gt is obvious, and the variance in gross tonnage is equally large. The outliers of note here are the Corsair Yachts’ modern classic Nero at 90 metres and 1,413gt and the 2019 Silver Yachts’ Bold at 85metres and 1,504gt at the other end of the scale.

Outside these ranges, there are some other noticeable trends in the percentage shifts in gross tonnage since 2000. The Superyacht Agency developed a different model for analysing this shift. The gross tonnage percentage graph outlined compares the historic fleet (2000-2020) with the past four years (2021-2024) and order book. For the purposes of this analysis, the fleet has been broken down into smaller 5-metre segments.

The percentage shift seen in the graphic below shows the significant increase in gross tonnage for smaller yachts between 2021-2024 (plus orderbook) in comparison to 2000-2020, most drastically in the 30-35-metre bracket (13.7 per cent) and the 35-40-metre bracket (10.8 per cent), suggesting a trend towards more volume from these smaller yachts.

There is a notable decline in gross tonnage for vessels ranging between 50 -55 metres (12.5 per cent), 80-85 (7.9 per cent) and 85-90 metres (14.3 per cent). These declines correspond closely to the scatter plots of gross tonnage vs LOA and the concentration of yachts that are engineered to keep their gross tonnage below the 500gt and 3,000gt regulatory thresholds respectively.