A Billion Dollars Isn't Cool: 74 Asteroids Worth Over $10 Trillion

Very cool!

But what does "accessibility" mean? The tool tip isn't helpful. What's the scale? Is it linear, exponential, or logarithmic? What are the end points? I.e., does a bigger number here mean it's more accessible or less accessible than a smaller number?

Also, could you please explain how you're calculating the cost of extraction and transportation?

Thank you for putting this together!