Historical clue formulations

• Cheery "Ciao!" — 2021-12-12
• "Ta-ta!" — 2016-06-05
• "Ta-ta!" — 2014-02-02
• "Ciao!" — 2011-09-08
• "Ta-ta" — 2007-08-12
• "Later!" — 2002-08-09
• "Bye!" — 1998-10-11
• Ta-ta — 1994-08-16