Magnitude and time variability of the 60 candidates (points with error bars, red square: J-GEM17btc, magenta upward triangle: J-GEM17bog, blue downward triangle: candidates with ROSAT detection, cyan diamond: candidates with NVSS detection, and green circle: the others) and the theoretical kilonova models with an ejecta mass of 0.01 M_⊙ at 40 Mpc (points connected with lines, Tanaka et al. 2014, 2017). The models represent dynamical ejecta (diamond), and wind with Y_e = 0.25 (square) and 0.3 (pentagon). Filled marks correspond to 1 d after the merger and open marks correspond to 2, 3, 4, and 5 d after the merger. (Color online)