step_ahead,prediction 1,12.873145230580121 2,12.657423304487018 3,12.499150880984962 4,12.50336081124842 5,12.800557270087301 6,13.06346470415592 7,12.63564171437174 8,12.63048737058416 9,12.679474517703056 10,12.555320406518875 11,12.6679041698575 12,12.54257924966514 13,12.683924764208495 14,12.4412053598091 15,12.598726795054972