If you don't apply for naturalization, how long do you have to stay in the United States at least every year to keep your American green card?

According to the immigration law, green card residents who apply for citizenship must live in the United States for at least two and a half years and at least six months each year five years before applying for naturalization. /kloc-if you leave the United States for more than six months per year, the remaining months will not be counted as two and a half years of residence. If you leave America for more than 1 year, the calculation of residence time will be interrupted.

If a green card resident needs to live overseas for a long time because of his work, but does not want to lose his citizenship, he can first apply to the Immigration Bureau for exemption from the restriction on the residence time of the green card in the United States on the legitimate grounds of being employed by an American company and being sent to work overseas, but the company he belongs to must be an American company, not an overseas company.

There will be no time difference. As long as there is. It is good to have a record.