2010 SO16 causes quakes May 9-12 every year

http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2010%20SO16;orb=1;cov=0;log=0;cad=0#orb
Horseshoe orbit

UPDATE: 6.9 quake on May 10th

2011  05 09 185442.52 -56.61  147.84   1  6.1  
2011  05 10 085509.11 -20.24  168.26  11  6.9
2011  05 13 233553.02  37.42  141.32  35  6.1  
2011  05 14 210722.34  36.44   70.75 207  6.0   
2011  05 15 130812.49   0.46  -25.60  10  6.1    
2011  05 15 183710.72  -6.16  154.45  43  6.5

05/09/10 7.2
05/16/09 6.5
05/12/08 7.9
05/16/07 6.3
05/16/06 7.4
05/10/06 6.4
05/14/05 6.7
05/12/05 6.5
05/10/05 6.3
05/13/04 6.4
05/14/03 6.7
05/13/03 6.3
05/09/03 6.3
05/11/02 - no quake
05/09/01 6.3
05/12/00 7.2
05/10/99 7.1
05/16/98 6.9
 05/13/98 6.6
 05/10/98 6.3
05/13/97 6.5
 05/11/97 6.5
 05/10/97 7.3
05/11/96 6.3
05/16/95 7.7
 05/14/95 6.9
 05/13/95 6.6
 05/08/95 6.4
05/11/94 6.5
 05/10/94 6.9
05/15/93 6.9
 05/13/93 6.9
 05/11/93 7.0
 05/17/92 7.3
 05/15/92 7.2
 05/12/92 6.7
05/19/91 7.0
05/12/90 7.2
 05/11/90 6.3
 05/08/90 6.5