This is a question about evolution of weapons technology. Destroyer is a class of ships which exists already for more than a century. One of its main characteristics is speed (these are generally the fastest large surface displacing vessels). Here is a little table of typical destroyers maximal speeds (in knots) arranged by years (name, year, power in 1000shp, max speed):
Cossak (1885) 14, 26,
Wickes (1917) 25, 35.3
Clemson (1918) 28, 35.5
Fubuki (1926) 50, 38
Fantasque (1935) 74-81, 40 (the fastest ever built)
Sims (1937) 51, 37
Fletcher (1941) 60, 36.5
Adams (1964) 52, 33
Spruance (1980) 80, 32.5
Arleigh Burke (1988) 53, 30
The data is from Wikipedia. The length (the most important characteristic for speed) is roughly the same for most vessels, and does not show any clear pattern. It seems that all modern ones have max speed about 30. Can anyone explain this strange pattern? Speed becomes less relevant after the mid 30s? Why?
EDIT. Let me clarify and address some answers. I was not asking about nomenclature of the ship classes, or their names, or the age of sail. The question I wanted to ask was:
Why the top speed of the fastest (surface, displacing) ships shows such a strange pattern of evolution?
It looks like the navies do not care about high speed of their fastest ships since the late 30s, or at least that this is a secondary concern.
One answer suggests an interesting possibility that the data that I used are not reliable. Can anyone suggest a more reliable source of statistics?
EDIT2. Thanks to all who answered. All answers which really address the question split into two classes:
That the pattern I noticed does not exist in reality and comes from faulty data. (That is Fantasque, for example was not really faster than a 21st century destroyer).
That the max speed of destroyers in not an important concern for modern navies.
I do not know how to decide between these two. Not enough reliable data cited in the answers.