Comparative dates on which the Nationals notched their 51st win, each season:
2005 - 5th July (83rd match of season)
2016 - 6th July (86th match)
2017 - 7th July (86th match)
2014 - 13th July (93rd match)
2012 - 15th July (86th match)
2015 - 22nd July (93rd match)
2018 - 26th July (102nd match)
2013 - 27th July (105th match)
2011 - 31st July (107th match)
2007 - 5th August (111th match)
2006 - 11th August (115th match)
2010 - 15th August (118th match)
2008 - 30th August (136th match)
2009 - 18th September (147th match)
I heard on the radio broadcast last night that the announced attendance was 8,506 and the Marlins' average home attendance for the entire season was 9,739. I haven't heard of any MLB club averaging less than 10k over a full season in ages - this must be some sort of expansion-era record in the making.