Month Million Square Feet 1919-01-01 4.50000 1919-02-01 6.60000 1919-03-01 12.6000 1919-04-01 20.2000 1919-05-01 26.5000 1919-06-01 30.5000 1919-07-01 30.3000 1919-08-01 26.7000 1919-09-01 22.0000 1919-10-01 27.9000 1919-11-01 18.2000 1919-12-01 15.8000 1920-01-01 11.6000 1920-02-01 9.50000 1920-03-01 16.0000 1920-04-01 20.9000 1920-05-01 17.1000 1920-06-01 10.9000 1920-07-01 8.60000 1920-08-01 10.8000 1920-09-01 8.20000 1920-10-01 11.2000 1920-11-01 7.90000 1920-12-01 5.50000 1921-01-01 6.70000 1921-02-01 8.60000 1921-03-01 14.4000 1921-04-01 18.0000 1921-05-01 18.8000 1921-06-01 18.2000 1921-07-01 14.0000 1921-08-01 18.0000 1921-09-01 21.5000 1921-10-01 22.0000 1921-11-01 22.7000 1921-12-01 21.9000 1922-01-01 18.1000 1922-02-01 16.5000 1922-03-01 30.4000 1922-04-01 31.6000 1922-05-01 31.5000 1922-06-01 31.5000 1922-07-01 24.4000 1922-08-01 23.7000 1922-09-01 23.3000 1922-10-01 25.8000 1922-11-01 28.7000 1922-12-01 26.0000 1923-01-01 24.6000 1923-02-01 22.7000 1923-03-01 39.5000 1923-04-01 39.2000 1923-05-01 34.3000 1923-06-01 25.3000 1923-07-01 23.7000 1923-08-01 24.1000 1923-09-01 22.5000 1923-10-01 35.0000 1923-11-01 33.1000 1923-12-01 30.5000 1924-01-01 34.6000 1924-02-01 28.0000 1924-03-01 44.1000 1924-04-01 42.2000 1924-05-01 34.4000 1924-06-01 28.3000 1924-07-01 20.9000 1924-08-01 24.6000 1924-09-01 24.3000 1924-10-01 28.4000 1924-11-01 31.4000 1924-12-01 29.7000 1925-01-01 23.5000 1925-02-01 23.7000 1925-03-01 40.3000 1925-04-01 46.2000 1925-05-01 42.2000 1925-06-01 37.5000 1925-07-01 40.5000 1925-08-01 46.3000 1925-09-01 38.2000 1925-10-01 44.0000 1925-11-01 44.6000 1925-12-01 43.2000 1926-01-01 33.6000 1926-02-01 26.5000 1926-03-01 42.6000 1926-04-01 45.7000 1926-05-01 43.9000 1926-06-01 40.2000 1926-07-01 31.7000 1926-08-01 37.2000 1926-09-01 36.7000 1926-10-01 38.8000 1926-11-01 39.0000 1926-12-01 34.4000