Short form, 100% count- exact counts
STF1 - all persons by race, Hispanic Origin
A - States - Block Groups/EDs
B - States-Blocks plus MSAs
C- Nation-States-places 10,000+
D - Congressional District (98th)
STF2 - 26 race and Hispanic Origin groups
A - States -counties-places-tracts
B - States, SMSA, areas 1,000 or more
C- Nation to areas of 10,000 or more
Long form, Sample count- estimates
STF3 - all persons by race, Hispanic Origin
A- States - tract/BNAs
B - States-Zip Codes
C- Nation-States-places 10,000+
D - Congressional District (98th)
STF4 -up to 39 race - Hispanic Origin groups
A -States - counties-places-tracts
B - States, SMSA, areas 2,500 or more
C- Nation to areas of 10,000 or more
Summary level and other technical concepts pertaining to summary files are briefly described in our guide, Census Summary Files: Technical Issues.