Solid symbols: coefficients $v_{n}$, $n=2,3,4$,obtained from Fourier decompositions of charge-independent correlators, $R_{2}^{\rm (CI)}$,in the ranges $0.2 \leq |\Delta\eta| \leq 0.9$ (left) and $0.9 \leq |\Delta\eta| \leq 1.9$ (right). Open symbols; flow coefficients $v_{n}$ obtained with the scalar-product method according to Eq. (\ref{Eq:mth_sp}). Panels (c) and (d): Ratios of the coefficients $v_{n}$ values obtained from $R_{2}^{\rm (CI)}$ to those obtained with the scalar-product method. Vertical bars and shaded areas indicate statistical and systematic uncertainties, respectively.