A record number of Americans are renouncing their citizenship as they seek to remove the burden of filing complicated and costly tax returns simply for living in another country. Just over 1,000 Americans gave up their nationality in the three months from January to March. That’s a significant increase from the 670 who did so in the same time span last year, and it’s already one third of the way to matching the total number of Americans who renounced their citizenship in 2013.