What?
This is a follow-up feature to Location-based Demand: That system uses population numbers as the basis for traffic demand and applies a “trips per capita” factor to arrive at the absolute numbers for pax and cargo. These factors are already specific to each country, but are currently hard-coded. The idea is to generate these factors based on readily available economic data instead. Think GDP, Gini index and similar indicators.
Why?
This is particularly interesting for historic game worlds, as it allows to model traffic development over time with relatively little research work required. But it generally improves the location-based demand model and thereby helps in moving away from airport-based demand which we employ right now (which is very research-intensive and doesn’t work with historic settings at all at the moment).
When?
Anytime.