Kindly let me know whether Tax Rate is a matter of Political factor or Economical factor in the PEST factors. Since tax rate is linked with changes in political factors / conditions of the country. Also it is related to expense so it can be a matter related to economical factor as well.
The precise classification of tax in PEST (or PESTEL) doesn’t matter. PESTEL is really just a checklist and what’s important is that tax effects have been identified.
Similar considerations apply with eg social and technological: the social habit of browsing the internet v the technological development of the internet. Irrespective of how you identify it, the Internet may be an important environmental effect.