Reliable US yearly population and netmigration estimates by state from 1970 up to today
Census State to State Migration Flows are available from 2004 - 2016. Census's State Intercensal Tables: 2000-2010 has annual state population data over the 2000-2010 period. Combining this with Census's State Population Totals and Components of Change: 2010-2017 gives population series for back to 2004.