Based on the theory and method introduced before, this paper applied the rotation models to compute the sample rotation rate of sampling survey on vacancy rate of households in Shanghai.

包括分层抽样下样本轮换的估计量公式和最优样本轮换率的确定方法。再接着利用前面介绍的理论知识，结合上海市城镇住房空置率抽样调查数据进行实证分析。

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Nottingham City Council's own survey of the city centre put the vacancy rate at 17.4% last October.

BBC: Nottingham centre has 'most vacant shop space'

"Our own city centre survey of retail units from last October shows a vacancy rate of 17.4% which is in line with the national average, " said Mr McDonald.

BBC: Nottingham centre has 'most vacant shop space'

Temp vacancy growth slowed for the second month in a row, according to the survey.

BBC: Woman entering a job centre