[en] The method of recalculation from the muon multiplicity spectrum to the extensive air showers spectrum vs the total muon number, n_μ, is presented. The method allows the direct comparison of data obtained in different experiments with muon groups. The direct comparison of the data at n_μ > 1800 and n_μ = 75 - 650 has been carried out. The data in the region n_μ = 75 - 3500 agree better with assumption that the slope change in the energy spectrum of primary cosmic rays occurs at the same energy per nucleus E_c ≅ 3 · 10¹⁵ eV and the mass composition in energy range 10¹⁵ - 10¹⁷ eV is close to the one observed at 10¹⁴ eV