  The latest electroweak precision data are analyzed assuming the existence of
the fourth generation of leptons ($N, E$) and quarks ($U, D$), which are not
mixed with the known three generations. If all four new particles are heavier
than $Z$ boson, quality of the fit for the one new generation is as good as for
the Standard Model. In the case of neutral leptons with masses around 50 GeV
(``partially heavy extra generations'') the minimum of $\chi^2$ is between one
and two extra generations. The predicted value of the higgs mass $m_H$ in the
presence of the fourth generation can be made rather large. The quality of fits
drastically improves when the data on b- and c-quark asymmetries and new NuTeV
data on deep inelastic scattering are ignored.
