Most of the figures here are based on industry-standard Business Winstone benchmarks, and you'll find broadly similar results in magazine test reports and hardware web sites everywhere. You will also find variations. Usually these have to do with different system components. This is important, because the CPU is only one component out of the four or five that have a major impact on system performance, and measuring CPU performance alone isn't very helpful. It does mean that to use Winstone for precise comparison between different CPUs, you need to use similar or identical hardware.
All reputable reports detail their test procedures and hardware exactly.
Note that these are Business Winstone benchmarks for general-purpose use. For certain specialised applications it is more appropriate to use different benchmark measures. The first thing to notice is how small the differences really are. The figures, in other words, just confirm what we already knew - all modern CPUs are very fast and the speed difference between one and another is fairly minor. For years past we have pointed out that the Intel CPUs are clustered at the top and the bottom of the chart, with few entrants in the mid-range.