Month Dollars Per Ton 1914-01-01 13.5200 1914-02-01 13.9400 1914-03-01 13.8600 1914-04-01 13.7800 1914-05-01 13.7600 1914-06-01 13.7300 1914-07-01 13.7200 1914-08-01 13.7200 1914-09-01 13.7200 1914-10-01 13.5600 1914-11-01 13.3000 1914-12-01 13.3200 1915-01-01 13.2900 1915-02-01 13.2800 1915-03-01 13.2700 1915-04-01 13.2600 1915-05-01 13.2900 1915-06-01 13.3600 1915-07-01 13.5300 1915-08-01 14.6900 1915-09-01 15.4600 1915-10-01 15.6900 1915-11-01 16.4200 1915-12-01 18.3100 1916-01-01 19.1800 1916-02-01 19.0800 1916-03-01 19.4400 1916-04-01 19.4700 1916-05-01 19.3800 1916-06-01 19.3200 1916-07-01 19.3000 1916-08-01 19.2800 1916-09-01 19.6000 1916-10-01 21.1800 1916-11-01 26.6400 1916-12-01 31.6200 1917-01-01 31.7800 1917-02-01 32.0600 1917-03-01 34.4500 1917-04-01 39.9000 1917-05-01 42.9300 1917-06-01 51.1000 1917-07-01 54.1400 1917-08-01 52.4600 1917-09-01 45.4800 1917-10-01 34.7100 1917-11-01 34.7100 1917-12-01 34.7100 1918-01-01 34.7100 1918-02-01 34.7100 1918-03-01 34.7100 1918-04-01 33.8400 1918-05-01 33.8400 1918-06-01 33.9400 1918-07-01 34.0800 1918-08-01 34.0800 1918-09-01 34.0800 1918-10-01 34.7600 1918-11-01 34.7600 1918-12-01 34.7600 1919-01-01 31.7600 1919-02-01 31.7600 1919-03-01 30.5700 1919-04-01 27.5100 1919-05-01 27.4700 1919-06-01 27.3400 1919-07-01 27.3400 1919-08-01 27.5100 1919-09-01 27.5800 1919-10-01 27.6500 1919-11-01 30.1600 1919-12-01 36.0400 1920-01-01 39.2600 1920-02-01 42.6300 1920-03-01 42.4500 1920-04-01 43.1700 1920-05-01 43.9000 1920-06-01 44.5900 1920-07-01 46.2500 1920-08-01 48.3900 1920-09-01 49.2000 1920-10-01 46.1500 1920-11-01 38.9900 1920-12-01 35.4800 1921-01-01 32.1800 1921-02-01 29.4200 1921-03-01 26.2500 1921-04-01 24.9600 1921-05-01 24.0300 1921-06-01 22.7700 1921-07-01 21.1800 1921-08-01 20.1700 1921-09-01 20.7300 1921-10-01 20.7700 1921-11-01 20.6000 1921-12-01 20.2500 1922-01-01 19.7300 1922-02-01 19.4100 1922-03-01 19.4700 1922-04-01 21.1000 1922-05-01 25.0600 1922-06-01 25.5400 1922-07-01 25.0300 1922-08-01 27.9900 1922-09-01 33.6000 1922-10-01 32.5100 1922-11-01 29.7700 1922-12-01 26.8600