In the movie Moneyball, there is a great scene where Billy Beane talks about the importance of a batter getting on base. The On Base Percentage (OBP) is the only thing he cares about when discussing potential players. Strong Towns and Urban3 have shown that Tax Value Per Acre is a corresponding metric for Cities. 
 

I understand that the higher tax value per acre is better in most circumstances, but what is the current tax value per acre?
 

Is there a way to calculate the tax value per acre for a city?

The city has a known area which can be found on Wikipedia and converted to acres. A financial report shows total property tax collected on all the parcels. And the mileage rate is published each year. 
 

The one thing I’m missing is how to convert a mileage rate and property tax collected into taxable value. Can anyone help me out with an equation?

A city could use this number to judge whether a property is helping or hurting the city’s financial issues. They could also use it to judge potential developments.

It would be interesting to look back and see how the city’s financial productivity has changed over time.