In my view, the best metric to consider is efficiency. Using the 15 years chart, we can see that DVRs were more efficient than MVR (at estimating endpoint MVR) over periods of 15 years starting between 1968 and 1983 and then between 1986 and 2007. The overall mean was 0.65 and the standard deviation was 0.23. Over 10 years, the results were not as good but that doesn't worry me. The results will be extended to include 2023, not sure when though.