After World War II ended in 1945, large numbers of non-Latvian workers entered the country, primarily to work at construction jobs. Among these non-Latvian ethnic groups, the increase in workers represented a population percentage shift of less than one percent before 1945 to more than three percent by the time of the Soviet Union's collapse. Which ethnic group shown on the chart best represents this shift?
1) Latvian
2) Russian
3) Ukrainian
4) German