Schemes	Normalized
Fou	${\tilde{ϕ}}_{f} = {\tilde{ϕ}}_{C}$
Sou	${\tilde{ϕ}}_{f} = \frac{{\tilde{x}}_{f}}{{\tilde{x}}_{C}} {\tilde{ϕ}}_{C}$
CD	${\tilde{ϕ}}_{f} = \frac{{\tilde{x}}_{f} - {\tilde{x}}_{C}}{1 - {\tilde{x}}_{C}} + \frac{{\tilde{x}}_{f} - 1}{{\tilde{x}}_{C} - 1} {\tilde{ϕ}}_{C}$
Quick	${\tilde{ϕ}}_{f} = \frac{{\tilde{x}}_{f} ({\tilde{x}}_{f} - 1)}{{\tilde{x}}_{C} ({\tilde{x}}_{C} - 1)} {\tilde{ϕ}}_{C} + \frac{{\tilde{x}}_{f} ({\tilde{x}}_{f} - {\tilde{x}}_{C})}{1 - {\tilde{x}}_{C}}$