Count everytime a node it shown in view
there is a module for that node view count, from module page: 


  Node View Count module allows to count node views. Unlike statistics module, this module records each view of node with user uid and timestamp. So now you can know how many times a user viewed node by day, week, month and etc.


This module is integrated with Views module. You can use it to create different statistics pages, output new not viewed nodes for user and many more.