Academic tool
Research Desk
Build a citable panel from US ocean Bills of Lading. Choose a research question, run it, then copy the SQL and cite the exact URL. On-screen results are for analysis. Matching bills can be downloaded as a paid extract ($0.0015 per record, $20 minimum).
All research tools
· Example paper
· Universe: kirchner.bols
Methods (read before you cite)
- US Customs ocean Bills of Lading only. Air, truck, rail, and informal entries are out of sample.
- Parties are filing names on the BOL, not resolved legal entities. Pick every name variant that is the same firm.
- Suppliers are distinct
shipper_namestrings after trim/upper, dropping blanks and tokens such as N/A. - HS codes are as filed. Product search uses case-insensitive tokens in
product_desc. - A year with few bills can be a filing-name hole, not a real exit. Inspect the yearly table before interpreting churn.
- Every result below is from the SQL printed under it. Nothing is imputed.
Firm panel · One importer over years
Product panel · A keyword or HS code
Supplier add / leave · Two periods, one importer
Start from a worked example