Historical clue formulations

• Is on the brink, say — 2025-07-05
• Isn't steady — 2023-09-24
• Rocks on the edge — 2018-09-27
• Almost falls — 2017-01-15
• Is on the brink — 2014-07-20
• Shows signs of instability — 2011-05-14
• Could fall either way — 2009-10-01
• Betrays unsteadiness — 2007-10-20
• Threatens to topple — 2005-02-27
• Is headed for a fall — 2004-06-01
• Wobbles on the edge — 2003-04-14
• Wobbles — 2003-02-28
• Prepares for a fall — 1995-01-12