Dinner Bill at City Tavern
Doug Gammell tells us that £89 in 1780 equals £9693 in 2011. This is obtained by multiplying £89 by the percentage increase in the RPI from 1780-2011. According to worth.com a pound in 2011 is equal to $1.59 U.S. dollars, so in 2011 the meal would cost approximately $15,400.