April 1 is Census Day but the Census Bureau began a daily posting of the mail
participation rate, that is the percent of forms sent out that have been mailed back.
These numbers for states, cities, counties and neighborhoods are on line at:
http://2010.census.gov/2010census/take10map/

As of this morning, the Mail Participation rates were as follows:

Nation 13%
State of Michigan 12%
City of Detroit 2%
Ann Arbor 4%
Southfiield 11%
Novi 12%
Farmington Hills 14%
Troy 18%