According to: LIFE Magazine
The BEATLES From Yesterday To Today
pg58 of the second printing 2001

On Aug.18 1964, when the Beatles arrived in San Francisco, to begin their first monster tour of America, 26 concerts were planned. Waiting for them was Charles Finley, the owner of the Kansas City A's Baseball team. Apparently, he had personally promised the kids of Missouri a Beatles concert. He first offered The Beatles manager $50,000. to add K.C. to the tour and was turned down. He then offered $100,000 and was still turned down. Finley finally writes a $150,000 check. This makes musical history, as the highest paid concert to date. On September 17th 1964, playing a thirty-two minute set to croud of about 20,000 in Kansas City Missouri, The Beatles made $4,838. a minute for their performance.