Historical clue formulations

• 24 heures ago — 2018-02-18
• Yves's yesterday — 2015-03-19
• Yesterday, to Yvette — 2011-08-27
• Yesterday: Fr. — 2004-03-30
• Yesterday, to Yves — 2001-08-29
• Yesterday, on the Yonne — 1995-10-08
• Yesterday: Fr. — 1994-05-23