Rain attenuation data at 19.5 GHz, obtained in a Japanese satellite wave propagation experiment at a measuring rate of 1 sample per second, are analysed. Short term duration statistics of attenuation and statistics of attenuation occurring in available periods, defined in CCITT [1] are derived. In deriving the attenuation statistics during available periods, the total period is divided into periods of available and unavailable times, for several attenuation threshold levels in accordance with the CCITT definition.