  The exponent $\lambda$ that describes the decay of the autocorrelation
function $A(t)$ in a phase ordering system, $A(t) \sim L^{-(d-\lambda)}$, where
$d$ is the dimension and $L$ the characteristic length scale at time $t$, is
calculated exactly for the time-dependent Ginzburg-Landau equation in $d=1$. We
find $\lambda = 0.399\,383\,5\ldots$. We also show explicitly that a small bias
of positive domains over negative gives a magnetization which grows in time as
$M(t) \sim L^\mu$ and prove that for the $1d$ Ginzburg-Landau equation,
$\mu=\lambda$, exemplifying a general result.
