Political Expediency
Every politician tries to put the best face on any... erm... challenge. But the Bush administration seems to have a Cabinet-level post dedicated to ensuring that all arms of government are on-message and positively spinning the Pres. The Daily Kos posts a lengthy section of an article from Roll Call about this month's announcement of the nation's poverty numbers, which ends up with these grafs:

The bureau's plan moved this year's release date from late September to late August -- a time when Members of Congress are normally home in their districts and many journalists are on vacation.

Then last week, Census officials announced yet another change: For what appears to be the first time, the figures will be released not by a career official but by the bureau's director, a political appointee.