What are the general guidelines for return per acre (in US$) for agriculture?

Question

I know that each crop has a different rate of return. I'm interested in valuation methods and sources both in general, and for specific crops (and livestock).

Answer 1

"No one can predict the future exactly, but agricultural economic analysis can assist farmers by identifying trends that might continue. "
...
"The analysis involved a time-path "forecast" framework, which is really a set of trend extrapolations, to address agricultural profitability. It focused on three key areas:

real product prices received by producers
crop yields per acre,
real costs of production per acre "

"For each price and yield draw, we can calculate the net return per acre to the farm."
http://www.card.iastate.edu/iowa_ag_review/fall_03/article3.aspx