  There exists and is unique up to multiplication by a constant function a form
of the highest dimension on the manifold of n-dimensional continued fractions
in the sense of Klein, such that the form is invariant under the natural action
of the group of projective transformations PGL(n+1). A measure corresponding to
the integral of such form is called a Mobius measure. In the present paper we
deduce an explicit formulae to calculate invariant forms in special
coordinates. These formulae allow to give answers to some statistical questions
of theory of multidimensional continued fractions. As an example, we show in
this work the results of approximate calculations of frequencies for certain
two-dimensional faces of two-dimensional continued fractions.
