A measured version of this already exists and gets little attention, which is a useful base rate. The WHO has published healthy life expectancy (HALE) next to life expectancy for two decades; the latest global figures are about 62 healthy years against 71 total (World Health Statistics, 2021 data), and the gap has been stable, so the number is tracked but it is not news. What would make a healthspan metric headline-worthy is something that moves it, and nothing yet has in a controlled trial: the first placebo-controlled lifespan and healthspan trials of anti-aging drugs in a species that shares our environment are the dog trials (TRIAD, Loyal's STAY study), reading out around 2029 to 2031, and the only regulator acceptance of healthspan or lifespan extension as an indication so far is the FDA's veterinary center, for dog drugs. If a drug ever does move the human number, the metric will get its attention; the dog results are the first signal on whether that happens before 2050. The arithmetic with sources (mine): https://w0lph.github.io/k9/why-dogs.html?v=2

Why the path to human longevity runs through dogs

Computed from the cited life tables and trials: a lifespan answer takes 4.6 years in dogs and 21 in people; dogs share our environment and diseases, lifespan has already been extended in dogs, and a regulator has accepted lifespan extension as an indication for dog drugs.

I doubt the seriousness of any metric that is called "gross domestic X" without a clear reason, just to piggyback on the well-defined notion of GDP.

Like, what is the net version of this "GDH" thing? One could in principle calculate net domestic product. What is its non-domestic version? We do always calculate gross national product.

If it needs marketing gimmicks like being named something nonsensical but familiar, it's probably not a good metric.

Looks like "wellbeing" may be the name of the game in the race to replace GDP: https://www.cambridge.org/nl/academic/subjects/economics/economic-development-and-growth/replacing-gdp-2030-towards-common-language-well-being-and-sustainability-community

Replacing GDP by 2030 | Economic development and growth

How did Gross domestic product (GDP) become the world’s most influential indicator? Why does it still remain the primary measure of societal progress despite being widely criticised for not considering well-being or sustainability? Why have the many beyond-GDP alternatives not managed to effectively…

Can you add a definition for your new metric?

@RobertCousineau Healthspan alone is not super well-defined today, so I would interpret GDH as the population aggregate of the amount of time each person spends in good health. (Something like Time * Quality, perhaps.) However, as a universal standardized measurement, it could fall into the usual overly-utilitarian pitfalls, which could have significant downsides, both easily foreseeable and less so.

Further reading at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6136295/

> "one common definition is that healthspan is the period of life spent in good health, free from the chronic diseases and disabilities of aging"

@cloudprism sounds good, the calculation was what I was looking for :) Do you have a plan for measuring relevance/attention/importance?

@RobertCousineau Something like a downtrend in references to GDP correlated to an uptrend in references to GDH across news articles, professional presentations, and academic publications. (Assuming we still have those in 2050.)