How Do Benchmark Numbers Work?

[inboardshooter]

I have a question about the numbers of benchmarking. I'm assuming, they're relative to a "reference" system, so I understand that. (Might have a actually read that a few years ago) But I notice the numbers keep getting larger. This is what I recorded during downtime at work:

9/29/2012 - Highest number video card benchmark 4,557 for $2,789.99. Second highest GeForce GTX 680 at 4,029 for $499.99.

Now I see the GTX 680 is at 5,548. Why is the 680 higher now? Do the numbers rise and sort of act like money, with inflation? For example, in 1 year from now, the numbers will be higher but not "worth" as much? Or do they grow in absolute terms, and 10 years ago the numbers were all in double digits or whatever they might have been?

I've only become a computer "enthusiast" in the past year or so I don't know what hardware benchmark numbers were even in the past 5 years.

[David (PassMark)]

You can find details about the video card benchmarks here,
http://www.videocardbenchmark.net/gpu_test_info.html
and here,
http://www.videocardbenchmark.net/graph_notes.html

The results are an average, so can go up and down a bit over time.

But in addition there was a very significant change around mid Oct 2012. We switched the charts from using PerformanceTest V7 results to PerformanceTest V8 results. The tests in PT8 are fairly different, for example there is now a DirectX 11 test and Direct compute test. So all the results moved around a bit on that day.