Jehovah's Witnesses have an active presence in most countries, but do not form a large part of the population of any country.
For 2017, Jehovah's Witnesses reported more than 8.45 million
publishers—the term they use for members actively involved in preaching—in 120,053 congregations.
[3] For the same year, they reported over 2 billion hours spent in preaching activity, and conducted Bible studies with more than 10.1 million individuals (including those conducted by Witness parents with their children
[295][296]).
[3] Jehovah's Witnesses estimate their worldwide annual growth since 2016 to be 1.4%.
[3]
The official published membership statistics, such as those mentioned above, include only those who submit reports for their personal ministry;
[297] official statistics do not include
inactive and
disfellowshipped individuals or others who might attend their meetings. As a result, only about half of those who self-identified as Jehovah's Witnesses in independent demographic studies are considered
active by the faith itself.
[298][299] The 2008 US
Pew Forum on Religion & Public Life survey found a low retention rate among members of the denomination: about 37% of people raised in the group continued to identify themselves as Jehovah's Witnesses.
[300][301] The study also found that 65% of adult Jehovah's Witnesses in the US are converts.
[302]
I got this from wikipedia