Age distribution of Her-Lyr candidates derived from the rotational period (black). In the gray data, rotational periods assessed from vsini measurements are included. From these measurements, a lower limit of the rotational speed is derived, leading to an upper limit of the gyrochronological age. In the top panel, the age is displayed on a linear scale, emphasizing the existence of a young concentration of 11 stars (18 including upper limits). In the lower panel, the age is plotted logarithmically to illustrate that the concentration of young stars consolidates with six (eight) stars with similar age. The binning of the histograms employs the Freedman-Diaconis rule (Freedman & Diaconis 1981).