Since the industrial revolution: years until most people had a technology

x linear, y log. 13 sourced crossings of 50% of the world, plus bounds and an AI projection.

source: Our World in Data (ITU internet; WHO clean cooking; WHO/UNICEF WUENIC vaccine coverage; World Bank electricity), GSMA (mobile subscribers 2015, smartphones 2023), ITU (TV households 2012), OpenAI posts (ChatGPT weekly users), Microsoft AI Diffusion reports, UN WPP 2024 • transform: Teal = share of all people; green = share of each year's newborns vaccinated (a different measure). Boxes = range from fuzzy intro and crossing years; dots = midpoints used in fits (least squares on log10 years). Gen AI bar = when ChatGPT weekly users alone would pass half of humanity, extending trends from Dec 2024 to Sep 2026 (exponential to linear); one product, so a floor for all AI. Fits stop at 2100: the lines reach 1 day and 1 hour far off-chart (see legend). • drawn 2026-10-21 02:50 UTC