Left: time evolution of the time derivatives of the mass accretion rate and of the MAD parameter. We show the results for aM94b100 and a94b100, but other simulations also exhibit similar behaviors. These two quantities, ﹩d\dot{M}/{dt}﹩ and dΦ _B /dt have opposite signs throughout the simulations. There is a clear anticorrelation between these two derivatives, shown in the right panels.