Before blindly using the files provided here, one should check the current recommendations TWiki.
The Run201*.json files provided here correspond to the UL recommendations for Run 2 analysis (2016, 2017, 2018) and are copies of the files found under /afs/cern.ch/cms/CAF/CMSCOMM/COMM_DQM/certification/Collisions1?/13TeV/PileUp/UltraLegacy/pileup_latest*.txt.
These files can be used ontop data n-tuples to store the pile-up information per event (in principle per lumi section, in practice per event) via:

• the stand alone applyPUlatest executable
  
• the mergeNtuples executable, which contains the applyPUlatest correction