Historical clue formulations

• Turns down — 2023-07-02
• Becomes less sharp — 2022-03-11
• Brings down — 2021-03-13
• De-lights? — 2020-11-08
• Turns down — 2020-08-08
• Loses luster — 2016-01-06
• Loses brightness — 2015-09-21
• Darkens — 2013-01-27
• Makes less bright — 2012-04-02
• Darkens — 2011-05-15
• Turns down — 2011-03-31
• Darkens — 2010-04-20
• Turns down — 2009-12-10
• Lowers, in a way — 2007-02-01
• Turns down — 2006-06-04
• Turns down — 2006-03-04
• Makes indistinct — 2004-12-26
• Darkens — 2004-09-26
• Darkens — 2004-02-13
• Turns down, in a way — 2002-11-22
• Turns down — 2000-09-17
• Lowers — 1997-06-13
• Lowers, as the lights — 1997-02-19
• Turns down — 1996-06-30
• Lowers, in a way — 1995-01-15