www.ipums.org -- Main webite
www.ipums.org/usa/samples.html -- Data Download Location

Note:  No 1890, 1930, 19801, 19901, 19904.
       For 1980 and 1990, 5% State samples are available for download
       as 51 separte files

ip18501.Z -- Free Population
ip18601.Z -- Free Population, preliminary sample
ip18602.Z -- Free Population w/Black oversample, preliminary
ip18701.Z -- General, preliminary sample
ip18801.Z -- General
ip19001.Z -- General
ip19101.Z -- General
ip19102.Z -- Black Oversample
ip19103.Z -- Hispanic Oversample
ip19201.Z -- General
ip19201.preliminary.Z 
ip19401.Z -- General
ip19501.Z -- General
ip19601.Z -- General
ip19701.Z -- Form 1 State ("5%" state)
ip19702.Z -- Form 2 State ("15%" state)
ip19703.Z -- Form 1 Metro ("5%" county group)
ip19704.Z -- Form 2 Metro ("15%" county group)
ip19802.Z -- 1% Metro (county group or "B" sample)
ip19902.Z -- 1% Metro (county group or "B" sample)
ip19904.Z -- 1% Unweighted (derived from 5% sample)
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