Alabama Univ old map survey result on the Website. survey for Sea of Japan description

I did serched how Sea of Japan part discribes on the old maps in Alabama Univ. Website .The result is as follows; I checkd from four category.
1.Continent
2.East Asia
3.SouthEast Asia
4.Japan

1550-1600 None discription.
1601-1650 China Sea 2(66%) Oriental Sea 1(33%) total 3
1651-1700 Oriental Sea 1(100%) total 1
1701-1750 Oriental Sea 2(22%) Eastern Sea 1(11%) Corea sea 2(44%) Japan Sea 4(44%) Total 9
1751-1800 Corea sea 10(76%) Japan Sea 3(23%) Total 13
1801-1850 Corea Sea 7(10%) Japan Sea 57(87%) Corea n Japan 1(1%) total 65
1851-1900 Japan Sea 77(100%) total 27
1901-1911 Japan Sea 27(100%) total 27
Gttl 145 Map list(Excel files)

In the result, It is almost match with the result with survey by Japan's Ministery of Foreign affairs （See here map inspection result on each libraries.).

There are no map found describes "East Sea". "Corean Sea"had increased from 1700-1800,It can be assumed by French Danville's report around 1820's from China to Europe by his map ,copied and translated from Chinese to French. on the other hand ,late of 18Century to early 19Century, Sea of Japan dominates of its own area name, .Assuming that La Perouse, Arrowsimith's reports promotes Sea of Japan name and Krusestern's comments determined the fate of the name of Sea of Japan. Sea of Corea or Oriental or Eastern Sea name had disappear, but "Corea"'s name succeed to Korea strait and Gulf Of Korea(Today's East Chosun Gulf/Bay)