"On the money” means “accurately” or “precisely” and has been cited in print since at least 1939. For example, an arrow that hits the center of a target is said to have been fired “right on the money” (or “dead on the money"). In basketball, a three-point specialist who hits a three-point shot is said to be simply “money.” An accurate and precise maneuver need not immediately result in a monetary reward to be “on the money.”
“In the money,” meaning that a money prize has been won, was popularized in horse racing (a horse that finishes first, second or third is “in the money") and has been cited in print since at least 1895.
(Oxford English Dictionary)
colloq. (chiefly N. Amer.). on the money: accurately, precisely; in just the right place, time, or manner. Usu. with intensifying adverb, as right on the money, dead on the money.
a1944 B. Stiles Serenade to Big Bird (1947) v. 36, I checked the oil pressure and tuned the RPM on the money.
1962 New Yorker 10 Nov. 145 You’ve got to be right on the money when you set it [sc. an aeroplane] down.
1972 Sat. Rev. 4 Nov. 28 Peter Klappert’s article ‘Let Them Eat Wonderbread’ on a political double talk from a poet’s vantage point was right on the money.
27 January 1939, Morning Advocate (Baton Rouge, LA), “Post Mortems in Sports” by W. I. Spencer, pg. 19, col. 5:
Big fellows who can ill afford to add on a lot of pounds were “right on the money” as far as their regular weights go.
June 1941, Flying Magazine, pg. 94, col. 2:
We were riding a 50-mph tail wind and really making time, every check point coming up right on the money.
September 1943, Boys’ Life, pg. 9, col. 2:
Two turns. Probably right on the money. Nice spin.
Google News Archive
28 November 1952, Lewiston (ID) Morning Tribune, pg. 8, col. 4:
Guest predictors in the Lewiston Morning Tribune poll on the outcome and probable score of the Lewiston-Clarkston prep football game were “right on the money” in picking the touchdown difference between the clubs.
OCLC WorldCat record
Right on the money : the definitive guide to forecasting foreign exchange rates
Author: Adam Hewison
Publisher: Arlington, Va. : Infinite Data, Inc., ©1990.
Edition/Format: Book : English
New York City • Banking/Finance/Insurance • (0) Comments • Wednesday, May 23, 2012 • Permalink