Relation between rotational and cycle periods. The cycles we obtained from the long-term photometry data for EK Dra are marked by red diamonds. The cycles for stars denoted in purple are taken from Oláh et al. (2009). The rest are adopted from Oláh et al. (2016), who distinguished between simple cycles (light blue circles), complex cycles (dark blue squares), and additional cycles (black dots) to the complex ones. The solar cycles (Gleissberg, Schwabe, and 3–4-yr cycles) are marked in orange.