Hi Ed:
The 1970 Census data on the BEA website shows a separate row, at the
very end of each county's table, for "place of work not reported". So,
Cook County Illinois has 181,911 resident workers with place-of-work not
reported, in 1970. Part of the mystery is solved.
I believe all of the "standard" 1970 Census tabulations did NOTdo
place-of-work allocation (imputation), so we would always see the "not
reported" data for any county, place or tract.
The 1970 Urban Transportation Package (UTP) probably had some
allocation (imputation) procedure to allocate the "not reported"
area-of-work to whatever geographies were used after the 1970 Census.
This is a guess. I don't have extensive records of the 1970 process. [I
do have the "Urban Transportation Factbook" published by the American
Institute of Planners and the Motor Vehicles Manufacturers Assocation,
in 1974, but it appears to be based on standard census tabulations, not
the UTP....?] Perhaps the answers are hidden in the Census Bureau (maybe
Phil can find the info before he retires next Friday? Or perhaps the
answers are in the archives - - JJ McDonnell's papers, or Alan
Pisarski's office....Perhaps some information is in the TRB Special
Report #145 (the 1973 Albuquerque Census conference.)
Happy hunting,
Chuck
**************************************************************
Charles L. Purvis, AICP
Principal Transportation Planner/Analyst
Metropolitan Transportation Commission
101 Eighth Street
Oakland, CA 94607-4700
(510) 817-5755 (office) [new, 8/1/05]
(510) 817-7848 (fax) [new, 8/1/05]
www:
http://www.mtc.ca.gov/
Census WWW:
http://www.bayareacensus.ca.gov/
**************************************************************
>> Ed Christopher <edc(a)berwyned.com>
02/21/07 8:40 PM >>>
Our friends (who I do not know) at the Bureau of
Economic Analysis who
do the Regional Economic Accounts revamped their historic (1970, 1980,
1990 and 2000) Journey to Work (JTW) data base and put a nice search
engine to it. For years I have sent people to the BEA sight for JTW
flows but with the new search engine and the 2000 data it is so easy
to
use. For 2000 they have added flows by major industry at the county
level and by minor industry at the state level. You really need to
check it out.
http://www.bea.gov/bea/regional/reis/jtw/
But then there is the nagging issue. Why do my historic CTPP/UTPP
numbers and BEA not match. In 1970 and 1980 the two sources look to
be
off in different directions, but for 1990 they match and for 2000 it
looks like a small rounding difference. Getting into the detail,
attached is a comparison of the BEA/CTPP-UTPP numbers for Cook county
IL, specifically the Cook to Cook flows. In 1980 BEA is about 2K
higher
out of 2M, but in 1970 BEA is in the neighborhood of 200K low. I know
this keeps coming up, but why? Is the pattern the same around the
country, BEA is high in 1980 and low in 1970? At some point we may
need
to reconcile all this and pick one series or the other. Since I have
been tracking the Chicago region numbers
(
http://www.berwyned.com/papers/co2cochgo.pdf) for quite some time
this
has always been a nagging headache.
How do all the numbers compare in your counties? Does anyone remember
why the 70s and 80s might not match? (please reply to all)
--
Ed Christopher
708-283-3534 (V)
708-574-8131 (cell)
FHWA RC-TST-PLN
19900 Governors Dr
Olympia Fields, IL 60461