Historical clue formulations

• It may be in the low 90s — 2025-10-28
• C8H18 — 2023-08-11
• Component of gasoline — 2019-10-21
• 87 is a common one — 2019-07-07
• Grade in the high 80s or low 90s? — 2018-06-30
• 87, 89 or 93, on a gas pump — 2018-01-23
• Station measure — 2017-12-29
• Measure of ping resistance — 2017-12-09
• It's usually in the 80s or 90s — 2017-03-30
• Fuel rating — 2014-09-10
• Gas rating — 2013-09-30
• 89 or 91, maybe — 2012-06-14
• Premium number — 2012-01-20
• Station identification? — 2010-07-25
• ___ rating — 2010-02-20
• 87 or 93 — 2008-05-11
• Station number — 2005-09-25
• Gas rating number — 2005-02-14
• Shell figure — 2003-02-27
• Gas pump number — 2002-08-06
• It's often in the 90's — 2002-04-26
• It may be in the low 90's — 2000-06-10
• Shell designation — 1999-05-13
• Gas pump rating — 1998-06-15
• Gas rating — 1998-06-02
• Numbered gas rating — 1998-04-28
• 87 or 93 at the pump — 1997-11-03
• 93, e.g., at the pump — 1996-09-09
• Gas rating — 1996-08-19
• 93, e.g. — 1995-12-17
• Gasoline rating — 1994-10-24
• Antiknock number — 1993-12-15