相对稳定阶段 meaning in Chinese

plateau
relatively stable stage

The report confirms previous observations that the prevalence of the epidemic is levelling out in many places , as death rates and new infections come into balance in countries such as lesotho ( see chart )
这份报告确认了以前的观测，即许多地区传染病的流行水平在死亡和新增感染速率达到平衡时会进入相对稳定阶段，例如在莱索托（参见表格数据）。
The first period is from 1958 to 1959 , which is its initial stage ; the second period is from 1960 to 1961 , which is its continuous adjustment stage ; the third period is from 1962 to 1965 , which is its relatively stable stage ; the fourth period is from 1966 to 1977 , which is its undulate stage ; the fifth period is from 1978 to 1985 , which is its gradual abolishment stage
一是1958年至1959年，为其初期兴办阶段；二是1960年至1961年，为其继续调整阶段；三是1962年至1965年，为其发展相对稳定阶段；四是1966年至1977年，为其发展较为波动阶段；五是1978年至1985年，为其逐步取消阶段。