1912 January $8.9493 February 8.9578 March 8.9019 April 9.0978 May 9.2696 June 9.1017 July 9.1119 August 9.1595 September 9.2157 October 9.4515 November 9.4781 December 9.5462 1913 January 9.4935 February 9.4592 March 9.4052 April 9.2976 May 9.1394 June 9.0721 July 8.9522 August 9.0115 September 9.1006 October 9.1526 November 9.2252 December 9.2290 1914 January 8.8857 February 8.8619 March 8.8320 April 8.7562 May 8.6224 June 8.6220 July 8.6566 August 8.7087 August 15 9.8495 September 9.7572 October 9.2416 November 8.8620 December 9.0354 1915 January $9.1431 February 9.6621 March 9.6197 April 9.7753 May 9.7978 June 9.7428 July 9.8698 August 9.8213 September 9.8034 October 9.9774 November 10.3768 December 10.6473 1916 January 10.9163 February 11.1415 March 11.3760 April 11.7598 May 11.7485 June 11.6887 July 11.5294 August 11.4414 September 11.7803 October 12.0699 November 12.7992 December 13.6628 1917 January 13.7277 February 13.9427 March 14.1360 April 14.5769 May 15.1208 June 15.4680 July 16.0680 August 16.3985 September 16.6441 October 16.9135 November 17.0701 December 17.5966 1918 January $17.9636 February 18.0776 March 18.0732 April 18.4656 May 18.9133 June 19.0091 July 19.1849 August 19.1162 September 19.0485 October 19.0167 November 18.9110 The groups that make up the index number are as follows: