The regions of existence of Anger states in an iron garnet film are plotted and investigated for the first time in a space of three controlling parameters: the frequency and amplitude of the alternating field and the magnitude of the static bias field. It is shown that the dynamic spiral domains differ significantly in their configuration and properties in different regions. A quantitative parameter involving the velocity of the domain walls and the "looseness" (sparseness) of the dynamic array of magnetic domains is introduce to characterize the favorability of conditions for the formation of spiral domains.