The following data report total, monthly U.S. gasoline sales in millions of dollars from January 2017 to December 2018. (To find the data, go to the site https://www.census.gov/retail/index.html#mrts, find "Monthly Retail Trade Report," then select "Time Series/Trend Charts.") Sales Year Month ($ millions) 2017 Jan $35,730 2017 Feb 34,072 2017 38, 722 2017 Apr 39, 073 2017 May 40, 839 2617 jun 40, 109 2017 Jul 39, 897 2017 Aug 41, 317 2017 41, 446 2017 41, 817 2017 40, 286 2017 Dec 40, 146 2018 Jan 39, 323 2018 37,477 2018 Mar 42, 748 2018 Apr 2018 May 48, 149 2018 Jun 47 , 646 2018 Jul 48 , 091 2018 Aug 48 , 933 2018 Sep 45 , 685 2018 48, 442 2018 43, 339 2018 Dec 39, 726 Click here for the Excel Data File d. Evaluate a seasonally adjusted trend forecasting model. What is the MAD? (Round your answers to 3 decimal places.) * Answer is not complete. Period Month Sales Year Month Trend Absolute ($ Million) Index Forecast Error Jan-2017 35,730 35,000.000 x 0.898 x 31,421.020 x 4,308.980 x Feb-2017 34,072 35,000.000 x 0.856 x 30,381.980 x 3,690.020 X Mar-2017 38,722 36,000.000 x 0.975 x 35,082.010 X 3,639.990 x JAWN Apr-2017 39,073 36,000.000 x 0.984 x 5 May-2017 5 40,839 Jun-2017 6 40, 109 Jul-2017 7 39,897 8 Aug-2017 8 41,317 Sep-2017 9 41,446 10 Oct-2017 10 41,817 11 Nov-2017 11 40,286 12 Dec-2017 12 10,146 13 Jan-2018 39,323 14 Feb-2018 37,477 15 Mar-2018 12,748 CA WN 16 Apr-2018 43,209 17 May-2018 48,149 18 Jun-2018 6 47,646 19 Jul-2018 48,091 20 Aug-2018 8 18,933 21 Sep-2018 9 15,685 22 Oct-2018 10 48,442 23 Nov-2018 11 13,339 24 Dec-2018 12 39,726 MAD= e. What are the monthly Indexes? (Round your answers to 3 decimal places.) Month Index f. Forecast sales for January, February, March, and April of 2019. (Round your answers to 2 decimal places.)