ITSA output, postintervention linear trend not giving t, P, or CI

[Patricia Moore]

I have Stata 12.1. When using itsa and adding posttrend, I do not receive t, P, or the 95% CI. (see example below) Is this because I need an updated version of Stata? Thank you.

Postintervention Linear Trend: 2015

Treated: _b[_t]+_b[_x_t2015]
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Linear Trend | Coef. Std. Err. t [95% Conf. Interval]
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Treated | -170.2381 22.3128 . . . .
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