Last week U.S. Citizenship and Immigration Services (USCIS) changed how it calculates unlawful presence for students and exchange visitors in F, J, and M nonimmigrant status who overstay a visa. Under a new memorandum, they will begin to accumulate "unlawful presence" days starting on the date their F, J, or M immigrant status expires. Under the old policy, they started accruing unlawful presence on the day USCIS discovered the violation.

Those who have accrued more than 180 days of unlawful presence during a single stay may be subject to a three-year or 10-year ban on readmission. Those who have accrued more than one year of unlawful presence, whether in a single stay or multiple stays, are permanently inadmissible if they attempt to reenter without being admitted or paroled.

In a press release, USCIS Director L. Francis Cissna said "USCIS is dedicated to our mission of ensuring the integrity of the immigration system. F, J, and M non-immigrants are admitted to the United States for a specific purpose, and when that purpose has ended, we expect them to depart, or to obtain another, lawful immigration status. The message is clear: These non-immigrants cannot overstay their periods of admission or violate the terms of admission and stay illegally in the U.S. anymore."

Visa overstaying remains a serious problem in the U.S. A 2017 USCIS report found that 739,450 people overstayed their visas in 2016, and almost 630,000 remained in the U.S. by year’s end. The actual number may be higher because the report does not cover those who entered through a vehicular or land port of entry.

By arrival category, student visa holders were the worst violators. Five percent of the 1.5 million student or exchange students overstayed their visas. The average rate in all visa categories was 1.5 percent. But with 50,437,278 visitors arriving through air and sea ports, the low overstay rate accounts for almost 740,000 illegal aliens.

It is estimated that forty percent of people in the U.S. illegally are overstaying visas.

Read more in UPI.

Updated: Mon, May 28th 2018 @ 1:15pm EDT