> To be fair it's not much (less than 5%)

https://www.eia.gov/tools/faqs/faq.php?id=427&t=3

Here's a better source. It's 0.5%. I felt that was enough to warrant using "not used in developed countries," but fair enough.

>Be careful about blanket statements unless you're an expert in the area because other HN readers are experts.

Easy there hotshot