The meaning inferred from the spin period distribution of normal pulsars
  We make statistics about the number distribution of normal radio pulsars according to the pulsar spin period. And find the physical meaning of the traditional statistical method about this problem is very limited. According to the statistical method proposed by us, the distribution rule is exactly the exponentially decay with the spin period increasing, especially important, which can be interpreted as normal radio pulsar number decays as the radiative elements decay. It discloses that though belonging to two different extreme scales of the universe and having different inner active mechanisms, the normal radio pulsars and radiative elements accord with the same varying rule. And like the half decay period of the radiative elements we can also introduce the half decay spin period of the normal radio pulsars. 
Ying-Chun Wei, Cheng-Min Zhang, Yong-Heng Zhao, Qiu-He Peng and Xin-Ji   Wu
astro-ph.SR