X-12 Seasonal Adjustment Error Message

[EVantmurph]

Hi

I want to seasonally adjust a quarterly seried which runds from 1952q1 to 2012q2. I got the following error message:

ERROR: Number of years spanned by the forecast augmented series (61)
exceeds program limit (60). See section 2.7 of the X-12-ARIMA
Reference Manual.
No seasonal adjustment this run

What should I do?

Thanks,

Anthony

[EViews Gareth]

Choose a forecast length less than 60.