2008-03-31   4.260
2008-04-29   3.030
2009-11-06   3.420
2010-02-11   3.520
2010-04-01   3.330
2010-05-31   4.100
2010-12-08   3.250
2012-01-16   2.430
2012-04-20   2.820
2013-01-03   3.730
2013-03-13   3.690
2013-06-16   3.810
2015-01-14   3.540
2015-11-30   3.760
2017-02-10   2.800