So-called P-Pdot diagram, which shows spin period (P) vs spin period derivative (Ṗ) for the radio loud (triangles) and the radio quiet magnetars considered in this work (circles). The values are taken from from Olausen & Kaspi (2014). Additionally, two death lines are shown: simple dipolar field magnetic field (upper line) and a twisted magnetosphere (bottom line). The area in between is referred to as the death valley.