GDP Misses Cheap But Essential Inventions

National income accounting grossly understates welfare gains because many of the most important inventions of the late 19th and 20th century—aspirin, light bulbs, water chlorination, anesthesia—were so inexpensive they made little impact on national accounts, yet we could not do without them; consumer surplus from such goods (e.g., anesthesia, for which the willingness-to-pay is effectively infinite) is enormous but uncounted.