Census of every prose-only duty line in the US Harmonized Tariff Schedule: 550 of 23,193 HTS lines carry no numeric rate, only sentences like "the rate applicable to products provided for in preceding subdivisions". The article sorts them into six resolution patterns and shows how to compute each effective rate from primary sources. Maintained as part of a free tariff-data project; the full table with source timestamps is here: https://exportsonar.com/guides/nonstandard-duty-rate-text-guide.html?src=lemmy-dbzer0