(NEW YORK) -- In honor of Valentine's week, Billboard has compiled a list of the biggest duets of all time, and coming in at number one is "Endless Love," by Lionel Richie and Diana Ross.
The magazine came up with the list by ranking each song on a point system based on its performance on the Billboard Hot 100 chart. The more weeks a song spent at number one, the more points it would get. In addition, each song had to be a true duet, with equal vocal time given to both singers.
"Endless Love" won because it spent nine weeks at number one and stayed on the over chart for 27 weeks which, back in 1981, was a very lengthy run.
The song that came in at number two on Billboard's list isn't exactly a love duet -- it's "Say, Say, Say" by Paul McCartney and Michael Jackson. McCartney's other famous duet, with Stevie Wonder, "Ebony & Ivory," is in at number four, just behind Brandy and Monica's "The Boy Is Mine."
Also making the top 10: Kenny Rogers and Dolly Parton's classic "Islands in the Stream," which is number nine, and "Don't Go Breaking My Heart" by Elton John and Kiki Dee, which is number 10.
Other famous duets which made the list farther down include "Up Where We Belong," "Stop Draggin' My Heart Around," "You're the One That I Want," "Baby Come to Me," "Easy Lover" and "(I've Had) The Time of My Life."
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