Version 2004.04.13


Description of Stata dataset:  parts_imports_7201_20040413.dta


This Stata dataset contains U.S. intermediate manufacturing imports at the four-digit SIC level of aggregation (1987 revision) from 1972 to 2001.  Intermediate imports are defined here to be the sum of product-level U.S. imports (TSUSA categories for 1972-1988; HS for 1989-2001) that contain variants of the word “part”.  For a list of these products see the Intermediate Goods Indicator file posted on my international trade resources webpage.  The product-level data were aggregated to industry-level data using the procedure outlined in:


Feenstra, Robert, John Romalis and Peter K. Schott.  2002.  “U.S. Imports, Exports and Tariff Data, 1989 to 2001.”  NBER Working Paper 9387.


The data in this dataset have the following format


year                              year of data

SIC87                          four-digit industry code

parts_imports               sum of intermediate imports

total_imports                sum of all imports


If you use these data, please cite:


Schott, Peter K.  2004.  “Across-Product versus Within-Product Specialization in International Trade.” Quarterly Journal of Economics 119(2).


If you encounter any problems with these data, please let me know via email at