Historical clue formulations

• Lead-in to plop — 2019-06-11
• Splat preceder — 2017-10-29
• Lead-in to plop or plunk — 2017-09-27
• Start to "plunk" — 2015-07-01
• Flooey lead-in — 2014-02-20
• Lead-in to plop or plunk — 2013-08-05
• Plop preceder — 2013-03-07
• Prefix with plunk or plop — 2011-08-08
• Plunk preceder — 2010-11-25
• Prefix with plunk or plop — 2009-10-05
• Lead-in to plunk — 2008-12-24
• Plop or plunk preceder — 2006-01-26
• Plop preceder — 2005-08-21
• Plop starter — 2005-04-03
• Prefix with flop or plop — 2004-10-03
• Plunk preceder — 2003-08-31
• Prefix with plunk or plop — 2002-10-09
• Plop preceder — 2002-06-27
• Prefix with plop — 2002-06-21
• Plunk or plop preceder — 2000-08-19
• Plop preceder — 1997-09-04
• Plop or plunk starter — 1996-11-13
• Plunk preceder — 1995-10-04
• Splash or plunk lead-in — 1995-06-08
• Plop preceder — 1995-05-06
• Start for plop or plunk — 1994-12-25