0 0 0 Experimental Operational 1 1 November 1988 Operational 2 1 November 1993 Operational 3 2 November 1994 Operational 4 8 November 1995 Operational 5 6 November 1996 Operational 6 5 November 1997 Operational 7 4 November 1998 Operational 8 1 3 May 2000 Operational 9 8 November 2000 Operational 1 10 2 7 November 2001 Operational 2 11 3 5 November 2003 Operational 3 12 4 2 November 2005 Operational 4 13 5 7 November 2007 Operational 5 14 6 4 November 2009 Operational 6 15 7 15 September 2010 Operational 7 16 16 4 May 2011 Operational 8 17 17 2 November 2011 Operational 9 18 18 2 May 2012 Operational 10 19 19 7 November 2012 Operational 11 20 20 8 May 2013 Operational 12 21 21 14 November 2013 Operational 13 22 22 7 May 2014 Operational 14 23 23 5 November 2014 Operational 15 24 24 6 May 2015 Operational 16 25 25 11 November 2015 Operational 17 26 26 4 May 2016 Operational 18 27 27 2 November 2016 Operational 19 28 28 3 May 2017 Operational 20 29 29 8 November 2017 Operational 21 30 30 2 May 2018 Operational 22 31 31 7 November 2018 Operational 23 32 32 15 May 2019 Operational 24 33 33 6 November 2019 Operational 25 34 34 6 May 2020 Operational 26 35 35 16 November 2020 Operational 27 36 36 15 June 2021 Operational 28 37 37 15 November 2021 Operational 29 38 38 15 May 2022 Operational 30-254 39-254 39-254 Future versions Operational 255 255 255 Missing Operational