Month Million Square Feet 1923-01-01 11.0800 1923-02-01 14.6400 1923-03-01 19.8400 1923-04-01 19.6700 1923-05-01 23.6200 1923-06-01 15.3300 1923-07-01 12.9900 1923-08-01 12.3000 1923-09-01 13.1500 1923-10-01 12.9300 1923-11-01 13.0800 1923-12-01 13.7500 1924-01-01 11.4000 1924-02-01 13.5800 1924-03-01 16.2800 1924-04-01 14.5100 1924-05-01 15.9700 1924-06-01 12.9700 1924-07-01 11.0300 1924-08-01 12.4900 1924-09-01 13.2800 1924-10-01 14.7400 1924-11-01 14.7600 1924-12-01 13.7600 1925-01-01 15.7500 1925-02-01 10.8300 1925-03-01 17.6700 1925-04-01 19.7400 1925-05-01 20.1700 1925-06-01 18.6600 1925-07-01 19.6600 1925-08-01 23.4200 1925-09-01 23.0700 1925-10-01 20.4500 1925-11-01 19.1400 1925-12-01 19.1400 1926-01-01 17.9700 1926-02-01 14.4300 1926-03-01 23.6900 1926-04-01 20.8600 1926-05-01 19.4200 1926-06-01 18.3100 1926-07-01 20.1900 1926-08-01 20.7400 1926-09-01 21.6000 1926-10-01 18.7800 1926-11-01 16.5600 1926-12-01 16.3000 1927-01-01 15.5000 1927-02-01 14.1100 1927-03-01 22.7800 1927-04-01 22.1500 1927-05-01 19.4100 1927-06-01 19.0300 1927-07-01 18.3500 1927-08-01 17.5600 1927-09-01 15.8800 1927-10-01 18.0200 1927-11-01 14.3200 1927-12-01 13.9800 1928-01-01 15.6000 1928-02-01 15.4800 1928-03-01 17.8600 1928-04-01 25.2400 1928-05-01 20.6300 1928-06-01 25.0300 1928-07-01 23.4600 1928-08-01 21.1800 1928-09-01 21.8500 1928-10-01 23.3500 1928-11-01 19.7300 1928-12-01 17.2500