Historical clue formulations

• Sudden increase — 2026-03-16
• Big change in price or power — 2023-02-05
• Sudden rise — 2021-08-10
• Powerful swell — 2018-11-25
• Electrical anomaly — 2016-06-30
• Jolt of power — 2015-08-31
• Literally, with 39-Across, head doctor — 2014-11-13
• Increase in troop levels — 2009-08-24
• Kind of protector — 2008-02-15
• Power problem — 2007-12-11
• Power glitch — 2005-10-11
• Coastal resident's hurricane worry — 2005-10-07
• Power glitch — 2003-05-06
• Computer hazard — 2001-06-15
• Power problem — 2001-02-24
• Sudden swelling — 1997-12-29
• Big polling news — 1996-03-30
• Billow — 1995-08-22
• Kind of protector — 1995-07-05
• Groundswell — 1995-05-07