(a) Plot the data on U.S. general aviation shipments. (b) Describe the pattern and discuss possible

Question:

(a) Plot the data on U.S. general aviation shipments. (b) Describe the pattern and discuss possible causes. (c) Would a fitted trend be helpful? Explain. (d) Make a similar graph for 1992-2003 only. Would a fitted trend be helpful in making a prediction for 2004? (e) Fit a trend model of your choice to the 1992-2003 data. (f) Make a forecast for 2004, using either the fitted trend model or a judgment forecast. Why is it best to ignore earlier years in this data set?

*U.S. Manufactured General Aviation Shipments, 1966-2003*

*Year*	*Planes*	*Year*	*Planes*	*Year*	*Planes*	*Year*	*Planes*
1966	15587	1976	15451	1986	1495	1996	1053
1967	13484	1977	16904	1987	1085	1997	1482
1968	13556	1978	17811	1988	1143	1998	2115
1969	12407	1979	17048	1989	1535	1999	2421
1970	7277	1980	11877	1990	1134	2000	2714
1971	7346	1981	9457	1991	1021	2001	2538
1972	9774	1982	4266	1992	856	2002	2169
1973	13646	1983	2691	1993	870	2003	2090
1974	14166	1984	2431	1994	881
1975	14056	1985	2029	1995	1028