Historical clue formulations

• Weak excuse — 2019-12-12
• Lame excuse — 2017-11-17
• Excuse for a lapse — 2011-07-11
• "It slipped my mind" — 2010-09-05
• Lame excuse — 2008-09-20
• "It slipped my mind!" — 2007-10-23
• "Oops" — 2003-05-24