It’s not only death dates. Take Syd Barrett for example; he stopped any involvement in music in the 1970s. Radio sessions he recorded in the 70s were commercially released in 1988 and 2004, and he died in 2006. The formula would have to be able to exclude those releases based on date relationships; as of now, those relationships haven’t been entered, so a calculated date would presumably say he was active through 2004.
I would much rather see manual dates that are filled in for only a few artists rather than calculated dates that will be flat our wrong in many cases.
One thing that could possibly be interesting could maybe be some kind of graph showing activity over years (maybe even on the main artist page? @chhavi?), which could possibly even have different colours for different types of activity? That could give an (automatically “calculated”) idea of artist activity, without necessarily stating it as “start” and “stop” dates.
I think maybe @loujin or @Leo_Verto has done something like this in one of their MB data visualisation projects?
Perhaps “active” is the period from their first paid preformance to their last paid performance - within the boundary of their life span (given that a release could be after they die)…