Top: the original figure from Frisch et al. (2013) showing the inferred temporal increase of the helium wind longitude. Bottom: our revisited set of appropriate measurements. Filled circles are the data points we consider for linear fits. Longitudes derived from PUI data (augmented by 2σ) serve only as upper limits. Shown are the central, upper, and lower trends allowed by the fits. Stationarity is contained within the solutions. The question mark corresponds to the IBEX period and the Witte et al. longitude, not included in the fit (the IBEX-Lo result is also not included, according to Sect. 2). PUI data points are slightly displaced in the figure to avoid overlap.