My favorite conspiracy theory I've heard gain surprising traction in some circles is that the world population is closer to 5B, not 8B. I think the theory goes that there's so much miscounting in third-world countries, combined with perverse incentives at every level to seem bigger than you actually are in second-world countries, that the final =SUM(B1:B195) Excel formula "they" run to get the world population is based on so many nested and poorly reported =SUM() formulas that the number is far more inaccurate than just "slightly".