What is the lifespan of a US 1 dollar bill?

Until a few years ago the average lifespan of a US dollar bill was 18-22 months. Recent changes in manufacturing the bills has increased that to about 36 months.

Roughly 45% of all US bills printed each year are dollar bills, and they have the shortest lifespan of any denomination.

All other major countries have eliminated their low-value notes in favor of coins. While coins cost more to produce, they stay in circulation for 30 to 50 years giving them much lower total lifetime costs.