Deal Lister

I have run my Sales Modle using SPSS 17.0 Forecasting Module(Creat Model - ARIMA) and got following output as attached. Could you please take a look and let me whether my model is fine and my forecasts is reliable?

Thanks!



==============================================================================================
PREDICT THRU YEAR 2009 MONTH 8.
* Time Series Modeler.
TSMODEL
   /MODELSUMMARY  PRINT=[MODELFIT RESIDACF RESIDPACF]
   /MODELSTATISTICS  DISPLAY=YES MODELFIT=[ SRSQUARE RSQUARE RMSE MAPE MAE MAXAPE MAXAE NORMBIC]
   /MODELDETAILS  PRINT=[ PARAMETERS RESIDACF RESIDPACF FORECASTS]
   /SERIESPLOT OBSERVED FORECAST
   /OUTPUTFILTER DISPLAY= [ BESTFIT(N=1)]   MODELFIT=SRSQUARE
   /AUXILIARY  CILEVEL=95 MAXACFLAGS=24
   /MISSING USERMISSING=EXCLUDE
   /MODEL DEPENDENT=Sales
      PREFIX='Model'
   /ARIMA AR=[1]  DIFF=1  MA=[1]  ARSEASONAL=[1]  DIFFSEASONAL=0  MASEASONAL=[1]
      TRANSFORM=SQRT  CONSTANT=NO
   /AUTOOUTLIER DETECT=OFF.

=============================================================================================

Model Statisticsa
Model	Number of Predictors	Model Fit statistics								Ljung-Box Q(18)			Number of Outliers
		Stationary R-squared	R-squared	RMSE	MAPE	MAE	MaxAPE	MaxAE	Normalized BIC	Statistics	DF	Sig.
Sales-Model_1	0	.575	.735	223201.712	11.913	133272.025	115.188	860324.498	24.837	19.074	14	.162	0

Forecasta
Model		Aug 2009
Sales-Model_1	Forecast	1983063.15
	UCL	2469178.51
	LCL	1537936.69