That depends on how many vCPUs are they running on each physical core for both x86 and ARM.
This will never be 100% scientific or correct since there are many factors that come into play, stuff like noisy neighbour for example.
What I'm trying to get is a ballpark idea of how their arm vCPU compares to the amd equivalent.
That depends on how many vCPUs are they running on each physical core for both x86 and ARM.