Interval              MPECS Discovery Observations
2007                      12         0           83
2008                      23         0          141
2009                      22         0          113
2010                      20         0          101
2011                      14         0           85
2012                      14         0          120
2013                      17         0          154
2014                      24         0          479
2015                      14         0          559
2016                      16         0          772
2017                      13         0          859
2018                       9         0          677
2019                       0         0            0
2020                       1         0            0