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This work is a continuation of our previous articles (Yermolaev et al. in J.Geophys. Res. 120, 7094, 2015; Yermolaev et al. in Solar Phys. 292, 193, 2017;Yermolaev et al. in Solar Phys. 293, 91, 2018), which describe the averagetemporal profiles of interplanetary plasma and field parameters in large-scalesolar-wind (SW) streams: corotating interaction regions (CIRs), interplanetarycoronal mass ejections (ICMEs including both magnetic clouds (MCs) and ejecta),and sheaths as well as interplanetary shocks (ISs). In this work we analyze theaverage profile of helium abundance N{\alpha}/Np for interval of 1976-2016. Ourresults confirm main early obtained results: N{\alpha}/Np is higher inquasi-stationary fast streams than in slow ones; it slowly changes incompression regions CIRs and Sheaths from values in undisturbed solar wind tovalues in corresponding type of piston (HSS or ICME); in Ejecta it is closed toabundance in undisturbed streams and it is maximal in MCs. We obtained forfirst time that N{\alpha}/Np correlates with plasma {\beta}-parameter incompression regions CIRs and Sheaths and anti-correlates in ICMEs. TheN{\alpha}/Np vs. {\beta} dependence is stronger in MCs than in Ejecta and maybe used as an indicator of conditions in CME formation place on the Sun.

Dynamics of Large‐Scale Solar‐Wind Streams Obtained by the Double Superposed Epoch Analysis: 4. Helium Abundance