  The attenuation of the electron shower size beyond the shower maximum is
studied with the KASCADE extensive air shower experiment in the primary energy
range of about $10^{14}-10^{16}$ eV. Attenuation and absorption lengths are
determined by applying different approaches, including the method of constant
intensity, the decrease of the flux of extensive air showers with increasing
zenith angle, and its variation with ground pressure. We observe a significant
dependence of the results on the applied method. The determined values of the
attenuation length ranges from 175 to 196 g/cm$^2$ and of the absorption length
from 100 to 120 g/cm$^2$. The origin of these differences is discussed
emphasizing the influence of intrinsic shower fluctuations.
