The post-1950s "petrochemical revolution" displaced natural materials (cotton, rubber, wood, paper, glass) with cheaper, scalable petro-derivatives in consumer and industrial goods.Many products qualify even with minor components (e.g., dyes, coatings, preservatives in "natural" items, or petro-derived reagents in pharma) 1900 5% 1950 25% 2000 75% 2025 95%