Complex sentence: According to the 2011 census, 2.2 million (73%) of usual residents of Wales were born there, two percent less than in 2001, The change can be attributed to both international and internal migration.
Split into simpler sentences: According to the 2011 census, 2.2 million (73%) of usual residents of Wales were born there, two percent less than in 2001. This change can be attributed to both international and internal migration.