As I did with the Japanese or British destroyers, I've now completed a study of the availability of the US Navy destroyers used in ww2.
I included in the scope the old Clemson and Wickes which had often been converted to other roles, and went up to all Allen M. Sumner class, and the part of the Gearing which commissionned before the end of the war.
This give me a total of more than 530 ships.
You'll find the same charts as I did earlier for other navies below with the state and (approximate) location of all ships for every month of the war, and I'll after that post some aggregate stats.
The color code is as follows :
* Light Green : European Theater of Operation (includes South atlantic & Mediterranean)
* Green : Pacific
* Light Blue : Non-DD role (generally APD, DM, DMS ...). There are two shades : the lightest denotes ETO, the other PTO
* Blue : Training, shakedown (more or less partial availability)
* Grey : building
* Brown : withdrawn or requalified as AG (auxiliary miscellaneous)
* Purple : unavailable
* Red : Sunk
* Orange : combat damage
* Yellow : non-combat damage
Regarding the location definition :
A : Atlantic, from Murmansk to South Atlantic; includes caribean sea & Gulf of Mexico
M : Mediterranean - the Torch ships of Nov 42 are labelled M, even though most of them did not technically enter the Med.
NP : North Pacific - includes the Kuriles Area
CP : Central Pac : from Hawaii to the Gilbert and the Palau
SP : South Pac : From the Fidji & Australia to the Solomon, New Guinea and up to Morotai
EP : East Pac : along the coast of America (North & South)
PI : Philippines (includes the forays in South China Sea in 45)
EI : East Indies
JW : Japanese waters : from Formosa to Hokkaido through the Bonins
CH : China coast
IO : Indian Ocean
Note that it is sometime difficult to find a location for a given month, especially with the fast-moving carrier task forces. For example, TF 38 raided Formosa in mid october 44, but I decided to list all ships in this force under the label 'PI', since the true purpose of those raids was the protection of the Leyte landings - and because of the battle of Leyte Gulf fought later in the month.
Anyway, the usual disclaimer apply : it has been done to the best of my knowledge under some atomicity constraints (the month as time-unit), and has no pretention of being a definitive work on this topic.
The main sources used have been DANFS (or wikipedia, which generally has the same info copy/pasted), destroyerhistory.org as well as dozen of OOB and hundreds of pages of different books I'm unable to list here.
BTW, while doing the information gathering, I found that the DANFS are overall pretty bad. Often the TROMs are short, there are many factual imprecisions (not to say blatant mistakes), and the general tone is too often far removed from neutral history.
Little game : list all ships present at Pearl Harbor on Dec 7th, read their DANFS history, count the number of aircraft they shot down according to DANFS (remove all "claims" and "asist", just keep the 'kills'). How many aircraft do we get ?
(Hint : that's more than the total number of lost japanese planes)
And now, on to the charts
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