Good racists, poor prophets

It's interesting reading some of these old racist works and seeing their predictions for the future. For instance, in The New Decalogue of Science, which I discussed briefly here, Wiggam on page 175 rhetorically asks of his audience

Do you know that there will never be more than just about one hundred ninety-seven million people in the United States? The credit for this brilliant demonstration belongs to Dr. Raymond Pearl of The Johns Hopkins University. This number will be reached by the year 2100--a short one hundred eighty years from now. Persons already born will have grandchildren who will see that day arrive.

I wonder, if the population was expected to be 197,000,000 in 2100, what they thought it would be in, say, 2105?