Forecast Pro	Minitab	NCSS		Statgraphics		Systat	Author's
Date	Auto	Manual	Auto	Manual	Auto	Manual	Manual	Auto
2007-Oct	65,352	66,028	65,041	63,808	65,205	66,366	66,553	66,166
2007-Nov	63,345	64,185	63,058	76,383	63,111	66,968	63,774	63,706
2007-Dec	64,767	66,146	64,363	77,586	64,516	67,574	64,371	65,058
2008-Jan	59,883	61,520	59,763	73,805	59,749	68,174	59,733	59,927
2008-Feb	57,875	60,874	57,538	71,048	57,950	68,780	58,467	58,777
2008-Mar	71,287	75,384	71,112	69,728	71,747	69,397	71,843	72,108
2008-Apr	67,801	72,498	67,780	71,729	68,603	69,993	68,468	68,700
2008-May	69,212	74,759	69,231	59,110	70,403	70,598	69,719	70,201
2008-Jun	72,619	79,445	72,533	60,444	74,179	71,204	73,253	73,946
2008-Jul	76,050	84,017	75,893	66,173	77,835	71,809	76,826	77,530
2008-Aug	74,059	82,702	73,828	63,497	75,720	72,410	74,658	75,704
2008-Sep	60,986	67,208	61,436	67,737	62,246	73,001	61,548	60,867
RMSE	2156.19	2215.66	2219.67	8187.40	2353.91	5693.04	1945.12	1923.82
Table 1 - Winters' method forecasts and RMSE from several programs. The Manual column implies the same three smoothing constants (a=0.54593, b=0.0001, g=0.0001) were used.