The article says: "More than 50 million copies are sold in a month in major countries of the world where Bible is read. This magazine is published by a reputable agency Jehovah’s Witnesses."
First, the WT is not sold but distributed (placed), free of cost to the recipient.
Second, it is apparently published by a "reputable agency" .... funny, not a religion organization but an agency....and one wonders why it is reputable
What is missing is how many of these free of charge WT's magazine end up unread in the garbage can.
Also, how did they measure popularity ??
Anyway, this is about US made magazines. I wonder if you would look at free newspapers in the UK for example or certain publications in China or India.