The number of Latvian inhabitants who left for the United Kingdom in the first quarter of this year is the highest since 2002, British government data show, and a University of Latvia professor predicts even more will have emigrated in the second quarter.

Mihails Hazans, who studies labor markets, made his prediction Sept. 11 during a presentation in Rīga of a soon-to-be-published book, EU Labor Markets after Post-Enlargement Migration, the daily newspaper Dienas Bizness reported.

In the first three months of this year, a total of 4,360 persons from Latvia registered for U.K. National Insurance Numbers (NINo). That is the highest tally of new registrations in a single quarter since 2002, according to data compiled by the Department of Work and Pensions.

The NINo is used in dealings with the British government and to track certain benefits, such as social security contributions. Persons living in the U.K. may apply for a number once they are 16 years old.

The data suggest the number of migrants from Latvia will continue to rise this year. In just the first three months of this year, the number of migrants had already reached nearly 55 percent of last year’s tally. During all of 2008, a total of 7,970 persons from Latvia registered for a NINo.

Since 2002, more than 51,000 persons from Latvia have registered for National Insurance Numbers. Migration to the U.K. exploded after Latvia joined the European Union in 2004. That year, 3,700 persons from Latvia registered for a NINo, but in 2005, the total shot to 13,500—a 264 percent increase. Although the pace of migration declined in the following years, thousands of Latvian inhabitants continued to leave for Britain: 11,420 in 2006 and 9,320 in 2007.

The British data do not necessarily track permanent immigrants, just people who are living in the U.K. According to Latvia’s Central Statistical Bureau, the number of permanent emigrants from the country last year totaled 6,007, less than the total who in 2008 registered for a NINo in Britain.

Since 2002, more than 4 million immigrants to the U.K. from around the world have registered for the insurance numbers, according to the Department of Work and Pensions. They include 10,280 from Estonia and nearly 113,000 from Lithuania.

The book, EU Labor Markets after Post-Enlargement Migration, suggests that workers from foreign countries have not in general displaced native workers or lowered their wages. Hazans is co-author of a chapter on the Baltic labor markets.

During his presentation in Rīga, Dienas Bizness reported, Hazans noted that the most recent emigrants from Latvia tend to have higher education and are heading abroad for good. Of those who emigrated in previous years, more than half have returned to Latvia after one year.

Hazans said the same trend might take place with current emigrants, but that state policies will have to be changed to foster return migration, Dienas Bizness reported.

The book, EU Labor Markets after Post-Enlargement Migration, is edited by Martin Kahanec and Klaus F. Zimmermann. It is being pubished by the Germany-based Springer.