Expect a knock on your door soon. The 7th National Census is already underway in Shanghai. The once-a-decade headcount of people inside China includes both Chinese citizens and, as of 2010, foreign nationals.

We heard from two people who have already been visited. The process is easy: the census takers knock on your door, identify themselves, and ask you to fill out a couple of questions on a paper, one paper per person in the household. The process takes a couple minutes at most. According to the government, questions for local citizens include "name, ID number, gender, marriage, education, profession and other information."

Foreigners answer slightly different questions; someone who already filled out the form was asked for a phone number but wasn't asked for ID or marital status. Other questions for foreigners included length of time in China, and purpose of stay in China. The form was in both Chinese and English, so no need to fumble with translation. Census takers on the ball!

If you haven’t gotten the knock yet, sit tight, there are over a billion people to count.