Historical clue formulations

• Leaves zip for a tip — 2021-05-16
• Large guard dogs — 2020-03-05
• Doesn't pay — 2018-03-04
• Doesn't leave a tip — 2014-03-10
• Leaves a 0% tip — 2012-02-15
• Cadavers, slangily — 2008-01-28
• Doesn't tip — 1994-09-15