This is an updated version of Urban Dynamics, the classic by Forrester et al.
John Richardson upgraded the diagrams and cleaned up a few variable names that had typos.
I added some units equivalents and fixed a few variables in order to resolve existing errors. The model is now free of units errors, except for 7 warnings about use of dimensioned inputs to lookups (not uncommon practice, but it would be good to normalize these to suppress the warnings and make the model parameterization more flexible). There are also some runtime warnings about lookup bounds that I have not investigated (take a look – there could be a good paper lurking here).
Behavior is identical to that of the original from the standard Vensim distribution.