Linear secular terms have been identified in both polar coordinates, independently of whether the latter have been derived from raw or smoothed observational data. After elimination, amplitudes and phases of the main harmonic terms in the polar motion have been determined. Our results back up assumption Chandler's cycle being non unique. Instead of one single peak, two close ones have unequivocally been identified within that cycle in spectro of polar coordinates. Their periods are: 1.171 and 1.198 years, respectively. In the Kimura's z-term, besides the well known annual cycle, a seml-annual one has been identified, whose amplitude is 3 to 4 times weaker.