@alan These are critical metrics in order to understand what is involved in maintaining #OpenStreetMap data. In the 2013-9 period we could manage maintenance through 1 hour mapping events before our pub meeting roughly ensuring systematic annual coverage of city centre POIs. It's harder to cover suburban POis in the same way.
We could do with an explicit way of capturing "I've seen this POI, and it's still there" without bumping the version with a check_date tag a la @streetcomplete. 2/3
@alan Remote mapping activities such as Maproulette challenges, typo fixing bots and tagfiddling, can artificially inflate the actual rate of change, and often add no new information. These can be difficult to identify if one is trying to analyse the underlying rate of change 3/3