An optical fiber including a multimode core having a radius, R1, and a maximum relative refractive index, Δ1MAX, at a wavelength λ0, an inner clad layer surrounding the core and having a radial thickness, T2, and a minimum relative refractive index, Δ2MIN, of about 0.0% at a wavelength of λ0, an intermediate clad layer surrounding the inner clad layer and having a radial thickness, T3, and a maximum relative refractive index Δ3MAX and an outer clad layer surrounding the inner clad layer and having a radial thickness, T4, and a maximum relative refractive index, Δ4MIN, at a wavelength of λ0. The optical fiber satisfies the following relationship: Δ1MAX>Δ3MAX>Δ2MIN, and the optical fiber exhibits an overfilled bandwidth of greater than or equal to about 1.5 GHz-km at λ0.