Over 90% of the relationships involve importing foreign brides with 57% coming from China while Cambodians and Vietnamese make up about 20% each. Most of the women go to relationship services to meet men in other countries. In short, they take their chances to secure a better economic future.
I was told that women are leaving the countryside for cities while some men stay with the families which leaves few opportunities for courtship. While this may be true, nearly a two thirds are living in populous areas. In short, I have no idea why there are so many mail order brides.
Update
I discussed this with some colleagues and they said that many of the Chinese brides are likely of Korean dissent. I am not sure if this makes any difference, but it is interesting.