  Systematic uncertainties in the light-element abundances and their evolution
make a rigorous statistical assessment difficult. However, using Bayesian
methods we show that the following statement is robust: the predicted and
measured abundances are consistent with 95\% credibility only if the
baryon-to-photon ratio is between $2\times 10^{-10}$ and $6.5\times 10^{-10}$
and the number of light neutrino species is less than 3.9. Our analysis
suggests that the $^4$He abundance may have been systematically underestimated.
