This might seem like a naive question from someone who doesn't know a whole lot about economics/government: Do governments have 'unified' computer models of the countries they govern, including for example energy generation, agriculture, transport etc.. A bit like simcity or civilisation games, but incredibly more realistic and complex. I have tried a few search terms in google but I feel I don't quite know what I'm looking for. The thought occurred to me after thinking about sustainable energy, and how you might convert to a sustainable energy economy. If there existed a model, you could simply play around with different scenarios and see the results. Or else you could search through possible parameter space to find the best configurations.