Table 7 Correlation between past Korean immigration and distance to Busan Port

Historical Korean immigrant size 1920

− 0.441

Historical Korean immigrant size 1930

− 0.292

Historical Korean immigrant size 1950

− 0.329

Historical Korean immigrant size 1955

− 0.316

Historical Korean immigrant size 1960

− 0.265

Historical Korean immigrant size 1965

− 0.218

Historical Korean immigrant size 1970

− 0.206

Historical Korean immigrant size 1975

− 0.208

Historical Korean immigrant size 1980

− 0.196

Historical Korean immigrant size 1985

− 0.183

Historical Korean immigrant size 2010

− 0.081