  We obtain a global existence result for the Einstein equations. We show that
in the maximal Cauchy development of vacuum $T^2$ symmetric initial data with
nonvanishing twist constant, except for the special case of flat Kasner initial
data, the area of the $T^2$ group orbits takes on all positive values. This
result shows that the areal time coordinate $R$ which covers these spacetimes
runs from zero to infinity, with the singularity occurring at R=0.
