Averaging over neutrino species, the invisible ${{\mathit Z}}$ decay width determines the effective neutrino coupling $\mathit g{}^{{{\mathit \nu}_{{{{\mathit \ell}}}}}}$. For $\mathit g{}^{{{\mathit \nu}_{{e}}}}$ and $\mathit g{}^{{{\mathit \nu}_{{\mu}}}}$, ${{\mathit \nu}_{{e}}}{{\mathit e}}$ and ${{\mathit \nu}_{{\mu}}}{{\mathit e}}$ scattering results are combined with $\mathit g{}^{{{\mathit e}}}_{\mathit A}$ and $\mathit g{}^{{{\mathit e}}}_{\mathit V}$ measurements at the ${{\mathit Z}}$ mass to obtain $\mathit g{}^{{{\mathit \nu}_{{e}}}}$ and $\mathit g{}^{{{\mathit \nu}_{{\mu}}}}$ following NOVIKOV 1993C.