Historical clue formulations

• da-DUM, da-DUM, da-DUM, da-DUM, for example — 2026-08-26
• Feet in a meter — 2024-09-12
• There are 70 in a Shakespearean sonnet — 2021-09-25
• "Above" and "beyond," e.g. — 2017-10-22
• Rhythmic feet — 2014-09-18
• Feet with rhythm — 2013-12-07
• "Shall I compare thee to a summer's day?" has five of these — 2009-10-27
• da-DUM, da-DUM, da-DUM — 2009-06-23
• Feet in a meter — 2008-05-14
• Poetic feet — 2005-03-14
• Feet, of sorts — 2004-01-21
• Pentameter parts, maybe — 2001-03-13
• Poets' feet — 2000-04-02
• Poetic feet — 1998-03-03
• Poetic feet — 1995-01-22
• Ogden Nash's feet — 1993-12-24