"But I only donate $20.00 every month"

Lets see [scratching my head]... $20.00 a month is $240.00 a year x 12,000,000 members = ~ $3,000,000,000.00 a year [very minimum, since there are only a few who donate very little but quite a few in Japan who donate more than $1000.00 a month]. 

This doesn't include SGI's special donation campaigns, other investments and businesses, including publications and their cemetery business. Of course, almost everything is  tax free. It wouldn't surprise me if their profit was more than $15,000,000,000.00 a year or more. Many companies are worth more than 20 x earnings. That would make SGI a $300,000,000,000.00 dollar company [not including their real estate investments, the largest in Japan].