Comparative dates on which the Nationals notched their 15th win, each season:
2017 - 26th April (21st match of season)
2016 - 29th April (22nd match)
2014 - 29th April (27th match)
2012 - 2nd May (24th match)
2013 - 2nd May (29th match)
2018 - 2nd May (31st match)
2005 - 4th May (28th match)
2010 - 6th May (28th match)
2011 - 6th May (32nd match)
2015 - 8th May (30th match)
2008 - 8th May (35th match)
2019 - 9th May (37th match)
2007 - 17th May (41st match)
2006 - 20th May (43rd match)
2009 - 2nd June (51st match)
