It's probably falls into the "Hard to Believe" category, but Jerry Lewis was one of the top box office stars of all time. From 1951 through 1963, Jerry Lewis made the list of Top 10 Money Making Stars 11 times, either with Dean Martin or solo, failing to make the list only in 1959 and '60.
Dino, himself, didn't make the list again until after the ebb tide of Lewis' screen popularity went out. Martin made the Top 10 List of Box Office stars twice as a solo act: Buoyed by the Matt Helm spy spoof series, he cracked the Top 10 in 1967 and '68, ranking #4 & #6, respectively.
Two years after making their film debut as supporting performers in My Friend Irma, Martin & Lewis were voted into the Top 10 in 1951, coming in at #2, topped only by John Wayne. It was the first of six straight years on the list. Ironically, 1951 was Abbott & Costello's last year in the Top 10. (Show business legend has it that Martin & Lewis were "discovered" by Abbott & Costello.)
The comedy team of Bud Abbott & Lou Costello, Martin & Lewis' only rivals as a comedic team in terms of box office popularity, had debuted on the list in 1941, the first of four consecutive years in the Top Ten, and were #1 in 1942. They also made the list in 1948, '49 & '50, seven times in total, one more than Martin & Lewis. However, by the early '50s, they definitely were suffering from over-exposure. Their career went into eclipse, as Martin & Lewis became America's comic darlings.
The year after being voted onto the money makers list by theater owners, Martin & Lewis duplicated Abbott & Costello's distinction by being named the #1 Box Office attraction in America. For the next four years, they were ranked #2 two straight years, then #7 and #6. In 1957, Jerry Lewis as a solo act cracked the Top 10 at #9 and was #3 the following year, his best showing without Dino.
Here is links to an excellent series on the Dean Martin-Jerry Lewis crack up, featured on Michael J. Hayde's blog BETTER LIVING THROUGH TELEVISION.
Aside from My Friend Irma & it's sequel, My Friend Irma Goes West (1950), Martin & Lewis appeared in 15 films from 1950 to 1956:
At War with the Army (1950)
That's My Boy (1951)
Sailor Beware (1952)
Jumping Jacks (1952)
The Stooge (1952)
Scared Stiff (1953)
The Caddy (1953)
Money from Home (1953)
Living It Up (1954)
3 Ring Circus (1954)
You're Never Too Young (1955)
Artists and Models (1955)
Hollywood or Bust (1956)