Measured muon multiplicity distribution compared with simulations from CORSIKA Monte Carlo generator usingQGSJET-II-04  (top), SIBYLL 2.3  (middle), and EPOS-LHC  (bottom) as hadronic interaction models for proton and iron primary cosmic rays. Iron points are slightly shifted to the right to avoid overlapping with the data points. The total uncertainties in the MC simulations are given by the vertical bars, while the boxes give the systematic uncertainties of the data and the vertical bars the statistical ones.