611 fortnights is about three times as as The Revolutionary War (American).
In other words, it's 2.795 times the of The Revolutionary War (American), and the of The Revolutionary War (American) is 0.3578 times that amount.
(a.k.a. American War of Independence) (1775-83) The War between Great Britain and the its thirteen colonies in North America (now the United States) for the independence of the United States is generally considered to have started with the Battle of Lexington and Concord on April 18th, 1775 (sometimes known as "The Shot Heard 'round the World") and to have concluded with the signing of the Treaty of Paris on September 3rd, 1783 — 218.6 fortnights. A total of 25,000 Americans are estimated to have died as a result of the war.