  The spectral weight of states induced in the Mott gap via hole doping in the
two-dimensional Hubbard model is studied within cluster dynamical mean field
theory combined with finite-temperature exact diagonalization. If the cutoff
energy is chosen to lie just below the upper Hubbard band, the integrated
weight per spin is shown to satisfy $W_+(\delta)\ge\delta$ ($\delta$ denotes
the total number of holes), in agreement with model predictions by Eskes {\it
et al.} [Phys. Rev. Lett. {\bf 67}, 1035 (1991)]. However, if the cutoff energy
is chosen to lie in the range of the pseudogap, $W_+(\delta)$ remains much
smaller than $\delta$ and approximately saturates near $\delta\approx
0.2...0.3$. The analysis of recent X-ray absorption spectroscopy data therefore
depends crucially on the appropriate definition of the integration window.
