Historical clue formulations

• "Obviously," in slang — 2021-06-13
• "You betcha!" — 2016-07-24
• "Of course!" — 2016-04-13
• "But of course!" — 2013-10-06
• "Why, of course!" — 2011-01-26
• "Why, certainly!" — 2011-01-03
• "But of course!" — 2008-12-22
• "But of course!" — 2008-08-19
• "Of course," slangily — 2006-08-07
• Breezy "Of course!" — 2006-03-29
• "Certainly" — 2005-01-19
• "But of course!" — 2003-04-03
• Slangy assent — 2002-10-26
• "Of course" — 2001-05-12
• "Of course!" — 1999-01-01