The number of non-bonding electrons of ${\mathrm{N}}_2$is_____

The outer electronic configuration of ${\mathrm{N}}_2$ is ${\mathrm{N}}_2\left(14\right):\mathrm{\sigma }1{\mathrm{s}}^2{\mathrm{\sigma }}^{*}1{\mathrm{s}}^2\mathrm{\sigma }2{\mathrm{s}}^2{\mathrm{\sigma }}^{*}2{\mathrm{s}}^2\left({\mathrm{\pi }}_{2{\mathrm{p}}_{\mathrm{x}}}^2={\mathrm{\pi }}_{2{\mathrm{p}}_{\mathrm{y}}}^2\right){\mathrm{\sigma }}_{2\mathrm{pz}}^2$
As evident, there are two electrons in the ${\sigma }^{*}1\mathrm{s}$ antibonding orbital and two electrons in the ${\sigma }^{*}2\mathrm{s}$ antibonding orbital.
Hence, the total number of non-bonding orbitals is four.