Historical clue formulations

• ___ alcohol — 2022-06-04
• Antiknock fluid — 2021-12-20
• ___ alcohol (fuel source) — 2021-05-31
• Kind of alcohol — 2021-04-03
• Kind of alcohol used as biofuel — 2019-07-28
• Kind of alcohol — 2019-04-11
• Kind of alcohol — 2018-12-30
• ___ alcohol — 2018-03-31
• Word on an old gas pump — 2016-04-28
• Car fuel additive — 2014-09-01
• Antiknock additive — 2013-08-11
• Kind of alcohol — 2011-01-27
• ___ alcohol — 2010-08-10
• Antiknock fluid — 2010-05-01
• Alcohol type used as biofuel — 2010-03-31
• Antiknock additive — 2010-02-04
• Kind of alcohol — 2009-04-19
• Kind of alcohol — 2008-04-06
• ___ alcohol — 2008-03-26
• ___ alcohol — 2006-08-08
• ___ alcohol — 2003-09-06
• Antiknock compound — 2003-08-25
• Gas additive — 2002-05-20
• Gas additive — 2001-07-02
• With 45-Down, C2H5OH — 2001-06-12
• Kind of alcohol — 2000-07-24
• Refinery product — 1999-06-24
• Word on old gas pumps — 1994-05-05