I am developing a new formula to determine a City's Economic Sustainability, or what I call a CESS Score, see below:

W= City proper population % growth rate over last 5 years.
X= Metro area population % growth rate over last 5 years.
Y= City proper average unemployment % rate over last 5 years.
Z= Metro area average unemployment % rate over last 5 years.

W^2 - X^2/ Y^2 - Z^2 x .25 = City Economic Sustainability Score or CESS Score. The score I came up for Oklahoma City was .748, which means Oklahoma City has a 74.8% chance of sustaining is current economic growth for the next 5 years.

However, I don't know if I have a good base indicator, please advise. I want to have this formula published, thank you.