David Ramsey Map Colelction survey for "Sea of Japan" description.

I checked Digital Archive on the David Ramsey Map colelction 4 categoly list and the result is as follows;
1.Asia
2.Japan
3.Korea
4.China

1651-1700 Oriental Sea 1 (100%) total 1
1701-1750 Oriental Sea 1 (9%) Korean Sea 7 (63%) Japan Sea 3 (27%) tootal 11
1751-1800 Korean Sea 9 (75%) Japan Sea 3 (25%) total 12
1801-1850 Korean Sea 17 (18%) Japan Sea 74 (81%) total 91
1851-1900 Japan Sea 39 (100%) total 39
1901-1911 Japan Sea 3 (100%) total 3
Gttl 157　Maplist(Excel File)

There are no map found describes "East Sea" Not so much difference with another survery incruding the result by Ministery of Foreing affairs of Japan, also 1701-1750, both Japan and Korea ,and other name is mix in various map, and 1750-1800 Korea name is increasing. Afterthe navigaton of La Perouse and Krusestern around Sea of Japan, 1801-1850 Sea of Japan dominates of its own name in the place of "Sea of Japan "Today.