Historical clue formulations

• "___ truly ..." — 2026-04-06
• Letter sign-off — 2015-10-14
• Letter closing — 2013-10-02
• "Cheers" alternative, in a letter — 2012-03-23
• Complimentary close — 2011-05-24
• Letter ender? — 2004-03-28
• Traditional letter closer — 2001-11-07
• Complimentary close — 1997-01-24
• Letter sign-off — 1994-09-14