Historical clue formulations

• Like a money-back guarantee — 2024-02-25
• Surefire — 2024-02-07
• Safe — 2022-01-15
• Like a sure bet — 2019-11-17
• Without a downside — 2015-09-02
• Like certain investments — 2011-10-23
• Like some investments — 2010-06-27