Do Arrangements of Public Domain Works Pay the Same Amount of Performance Royalties as Original, Non-Public Domain Works?

It's a bit complicated.

No - arrangements of public domain works can still be registered at your local PRO and generate royalties, however they will generate substantially less money than if you wrote and registered an entirely new original composition. The % earnings generated from a public domain work varies based on the PRO / society you are with.

For example, at ASCAP, Public Domain works are registered with a relative value of 10% rather than 100% for original, non-Public Domain works.

At BMI, Copyrighted arrangements of works in the public domain (classical and popular) will be credited at 20% of the otherwise applicable rate of payment for popular songs for all performances, with the exception of the Live Classical Concert distribution, where no payment is made for performances of arrangements of public domain works.