Are JW shy or afraid to express his religious affiliation in public statistics?

[Srecko Sostar]

From time to time, states are doing their census on population (population list). Listers come to people's homes and ask a variety of questions, conduct a survey. One of many questions is, to which religion you belong? The survey is "anonymous", that is, it is used only for the purpose of statistics. Also the answer is voluntary. Out of some of the 244 countries listed here, only in 37 countries there is evidence of Jehovah's Witnesses. Are they, JW, shy or afraid to express his religious affiliation in public statistics? In front of a man asking questions and writing it on paper?

How do you explain such a low representation of public information about JW members population, compared to WT Yearbook database numbers of members - book which will no longer be published :)) In few past decades i traveled to many European countries: Germany, Slovakia, Czech, Macedonia, Bosnia, Slovenia, Switzerland, Austria, Croatia, Hungary, Monaco, Montenegro, Serbia, Italy and Netherlands. In this CIA list only in Italy and Netherlands I have found report on JW regarding to countries i visited. 

CIA Library, The World Factbook , statistic about Country and Religions (%)

web link;

https://www.cia.gov/library/publications/resources/the-world-factbook/fields/2122.html