I have examined that census which is very comprehensive if you want to know the number of idiots in Pulaski County or the number of blind in Ashley County. But if you are looking for information on per capita income you are SOoL.
In 1860 people would have believed it unconstitutional to even ask about income.
It is good that you finally have studied the census data and its methodology.
Now it is time that you read what the economists of the time compiled.
I have already sent you the websites.
Please continue to read.