When a rate moves or a calculation changes, it gets an entry here. Numbers that quietly change underneath you are worse than numbers that were never there.
2026-08-22
First public version. MFN rates pulled from the USITC tariff schedule (2026 Revision 16) rather than transcribed, with duty modelled as stacked layers so each one can be traced and diffed separately. Section 301 forced labor rates from the July 2026 USTR notice: China and Vietnam 12.5%, India 10%.
2026-08-22
Packing invoiced separately from the goods is part of the dutiable value under CBP valuation rules. Treating FOB alone as the customs value understated duty on every unit. Packaging is now two inputs — paid before import, and added after — and only the first attracts duty.