NYC decade precipitation averages since 1870. 10 yr.............Ave. per year. lowest and highest year 1870's..............43.73"........39.25".......51.26" 1880's..............43.54"........35.37".......57.16" 1890's..............41.84"........35.37".......48.26" 1900's..............44.84"........37.44".......58.32" 1910's..............44.24"........33.72".......58.00" 1920's..............44.92"........37.76".......56.06" 1930's..............44.60"........33.85".......53.53" 1940's.............