Abstract: After the realization of soft landing,China’s economic growth is very stable and always keeps accumulating the energy for bouncing up.In 2003,the growth rapidly climbed to 9.1%,and this means the beginning of new business cycle with the characteristics of soft expanding.We used the Markov regime switching model to describe the dynamics of the stage of soft expanding,and found the evidences supporting the existence of bouncing effects in current situations.At the same time,we measured the duration of bounced effects and the asymmetry in the business cycle.The implications of tests are that we should still keep the procyclical policy and ensure the complete realizations of bounced effects.This is very helpful to the stage of soft expanding to be formed,solidified and finished.

Key words: business cycle, soft expanding, bouncing effects, regime switching model