U.S. citizenship renunciation-relinquishment and lawful permanent residency abandonment.

There has not been any detailed discussion of the number of LPRs who leave the U.S. annually.  The data provided by the U.S. Citizenship and Immigration Services reflects about 16 times more LPRs formally abandon their lawful permanent residency status by filing Form I-407 compared to U.S. citizens who renounce. The chart here shows a comparison for the years 2000 through 5/2013 of the total (i) USCs who have renounced compared to (ii) LPRs who have formally abandoned that status.
 http://www.dhs.gov/sites/default/files/publications/ois_lpr_pe_2012.pdf