We’re getting closer to the days when the Census request will go out to everyone. It’s probably a good time to remember the four different ways that we do the census for people who live in traditional housing units (i.e., not in group quarters like dormitories or assisted living facilities).

Mailout/Mailback The vast majority of households (about 90% of the population) will receive a census form in the mail via the US Postal Service. This partnership with the USPS has continued since 1970, when the first mailout/mailback US Census was conducted. We ask that you fill it out and mail it back by April 1.

Update/Leave In areas of the country (about 9% of the population) where mail is not delivered to residences uniformly, census staff will visited each housing unit, update our list of addresses, and leave a census form package in a plastic bag at the entrance door of the unit. This is the technique will we use in the Gulf Coast areas that were heavily affected by hurricane damage and are in the middle of their recovery.

Update/Enumerate Just like in remote Alaska, there are parts of the US (about 1% of the population) that both don’t uniformly receive mail at their residence and are far from any town. Some of these have demonstrated very low return rates of questionnaires in the past. In these areas, we will visit each housing unit and take a face-to-face interview with those in the household.

Large Military Installations At big military installations (e.g., Fort Bragg, NC) field work is coordinated with a military representative, and the Census staff is escorted to each housing unit to deliver the questionnaires. The military representative ensures that all questionnaires are returned.

The map below gives you an idea of how three of the four techniques are spread across the country. The blue areas are mailout/mailback; the tan areas are update/leave; the green areas are update/enumerate.