Historical clue formulations

• Accounting dept. stamp — 2022-06-30
• Document stamp abbr. — 2022-02-27
• Office stamp abbr. — 2017-09-23
• Mailroom stamp — 2014-10-12
• Invoice abbr. — 2013-03-16
• Shipping dept. stamp — 2010-04-20
• Office stamp — 2009-08-07
• Invoice abbr. — 2009-02-14
• Invoice abbr. — 2006-09-08
• Office stamp — 2006-06-16
• Invoice abbr. — 2005-11-09
• Bank stamp abbr. — 2005-07-27
• Shipping dept. stamp — 2005-06-26
• Office stamp abbr. — 2003-06-29
• Invoice abbr. — 2002-12-27
• In-basket stamp: Abbr. — 2001-05-02
• Invoice stamp — 2000-06-07
• Shipping dept. stamp — 1997-07-13