Historical clue formulations

• Level in an org. — 2016-03-05
• Command level: Abbr. — 2013-03-08
• Hierarchical level: Abbr. — 2013-02-21
• Command level: Abbr. — 2012-09-07
• Command level: Abbr. — 2003-01-17
• Command level: Abbr. — 2002-09-26
• Command level: Abbr. — 2000-09-29
• Level of hierarchy: Abbr. — 1997-02-01