Nebraska, a state to watch

I think Nebraska is a state to watch in these estimates. Last year was 178 bu/ac and conditions are better now than they were last year when yields were 178.

Last year 2-5-14-52-27
This year 1-4-11-57-27

I'm only getting 170 bu/ac out of the model. Was last year an unusual year? Have yields in Nebraska accelerated? Are the parameters I estimate for Nebraska showing to little difference between poor to good? (they are within 4 bushels of each other while excellent is ~40 bu/ac higher than that). I think this is one place where I could be badly off. Hopefully I've got other offsetting errors but if they did 178 bu/ac last year, can 180 bu/ac be out of the question this year?

Let me know what you think, post anonymously or send an email. I don't adjust the model in this simple exercise because I don't spend enough time analyzing all the information that is out there. These estimates were an attempt at being parsimonious, and this may be just one instance were some additional examination would lead one to a different conclusion about corn production in Nebraska.