I know we've had discussion before regarding how plausible it is for ship sizes to go up by certain amounts over a given time. Whilst browsing Wikipedia today I came across this chart, which I found rather interesting :
Link
It shows the growth in Royal Navy ships of the line - the largest most powerful ships in the fleet. As you can see, in 1630 the average ship of the line was around 1,500 tons. It then took over a hundred years for that figure to rise to 2,000 tons. By the 1830s, the tonnage of a battleship was up to about 2750 tons.
But then look what happened with the introduction of the steam/iron revolution. By 1880 the figure had jumped from 3,350 to almost 7,000 tons! I did a little sniffing around...
In 1871 HMS Devastation weighed in at 9,180 tons.
In 1889, HMS Royal Sovereign weighed in at 14,300 tons.
In 1905, HMS Agamemnon came along at 16,500 tons.
In 1906, HMS Dreadnought came along 18,120 tons.
In 1910, HMS Orion at 22,000 tons.
And so it goes. By 1936 the Nelson class weighed in at 34,000 tons. Within the next few years we'd see the Royal Navy more or less spent as a global force, but the USA brought in the Iowa class at 45,000 tons and the Japanese had the Yamato class at about 70,000 tons.
By this time the battleship itself was a spent force, with the Aircraft Carrier taking over. But there's no reason to suppose that the ships we saw in WWII were at the limits of construction. The planned US Montana class would have reached 66,000 tons, whilst Hitler had plans drawn up for a Battleship with 20 inch guns of a whopping 144,000 tons.
So it's perfectly feasible that we could have had a tenfold increase in ship sizes between 1900 and 1945, and that's including a pause in the 30s due to the Washington treaty limits; as soon as they went out the window ships ballooned in size at an incredible rate.
This trend continued, somewhat, with carriers. The WWII Essex carriers were around 33,000 tons; in the following fifty years the carriers tripled in displacement. However, over the last 20 years or so they have stayed the same size. I think this is largely because there is no competition; the great powers all constantly leapfrogged one another to build the biggest and best ships in the run up to the great wars, and this just doesn't happen now - pretty much nobody can afford it.
I'm thinking of working a version of that chart up with a bunch of the ships I mentioned and others on it, just for fun...







