Historical clue formulations

• "I'm not buying it" — 2016-04-30
• Deal-killing declaration — 2012-12-08
• Key phrase — 2011-02-12
• Register message — 2010-12-11
• Register button — 2009-09-04
• Old cash register key — 2008-09-07
• Key on an old register — 2008-09-01
• Deal-killing words — 2007-11-16
• Key on a cash register — 2007-08-24
• It's hit when making change — 2005-01-23
• Register button — 2002-12-08
• Cash register key — 2002-05-26
• Shopper's problem? — 2000-05-18
• Key phrase — 1999-07-24
• Cash register key — 1999-04-26
• Change-making key — 1999-04-11
• Register key — 1998-09-06
• Cash register key — 1997-07-22
• Register message — 1995-05-21