Historical clue formulations

• Record of money owed — 2026-06-07
• Notice of money owed — 2025-03-07
• I.O.U. — 2024-12-20
• I.O.U. — 2022-02-19
• I.O.U., e.g. — 2019-12-21
• "Pay me later" marker — 2016-08-09
• Debt memo — 2013-02-15
• I.O.U. — 2012-07-13
• Check — 2007-05-26
• Marker — 2006-07-13
• Slip in a pot — 2006-03-05
• IOU — 2006-01-16
• Marker — 2005-08-21
• Gambler's marker — 2004-09-14
• Voucher — 2004-04-04
• Voucher — 2001-10-29
• It might go into a pot — 1999-01-28
• It may be thrown into a pot — 1998-07-26
• Voucher — 1997-11-21
• I.O.U. — 1995-01-30
• I.O.U. — 1994-10-26
• l.O.U. — 1994-01-18