Data: Trade imbalance at the County level in the US I am looking for some source of data on trade imbalance at a county level in the US, preferably for years 1990-2007. Does anyone know if such data can be publicly available? Or any paper that have been using data like this? 

UPD: to break this down, I am looking for:


international import/export statistics by US county,
intra-state trade statistics, meaning shipments between counties within the US. 


Thanks in advance!
The data you're asking for doesn't exist.

Most data on things like this are captured through the taxing authority, which means that there are entities that want to collect taxes and therefore care very much where you do something and where your inputs came from. That's very true when there are international borders involved, and it's true to a much lesser degree when there are state borders involved, but in the US, there's generally no administrative interest in tracking the flow of goods across county borders.

Source: I used to create state and local area GDP estimates for the Bureau of Economic Analysis.