Electron density Saha Ionization Equation

[shahbaznihal]

Saha-Boltzmann equation describes the ratio of number densities between any two consecutive ionization states and its product with the number electron density i.e.
$$n_e\frac{n_{i+1}}{n_{i}}$$
Here, $n_e$ is the electron number density, $n_{i+1}$ is the number density in $i+1$ ionization state and $n_i$ is the number density in the $i$ ionization state. My question is regarding the factor $n_e$. Which electron density is this actually? Is it the electron density produced as a result of ionization from $i$ state to $i+1$?

 

[DrClaude]

It is the total electron density.