中文摘要：

在国家实行全面两孩政策背景下,认清生育意愿与生育行为的差异,是把握中国未来人口形势变化的关键。文章利用2010年以来的四次全国性抽样调查原始数据,对中国育龄人群的生育意愿与生育行为的差异及影响因素进行分析。研究发现：中国目前意愿生育水平在1.82~1.88的区间范围内,其点估计值在1.86左右,已显著低于更替水平;越年轻的出生队列其生育意愿越低,中国未来的意愿生育水平可能会继续降低;育龄人群的意愿生育水平要显著高于其终身生育水平,且二者差异随年龄的减小呈递增趋势,中国未来生育水平存在进一步下降的可能性;没有生育政策限制下的终身生育水平仅为1.68,这可以作为生育政策调整对中国生育水平影响的上限。生育政策对当前育龄人群生育意愿与生育水平差异的贡献度在33%左右,全面两孩政策对中国生育水平的提升作用有限。

英文摘要：

For the first time, China is beginning to loosen its rigid family planning policy nationwide by adopting two-child policy. However, this policy＇s effectiveness relies on a strong assumption： the existing family planning policy is the major determinant of people＇ s fertility behavior. Based on four national representative surveys since 2010, our estimate shows that policy constraint only accounts for 33% of the differenee between fertility intention and behavior, and the remaining variation is due to socioeconomic factors. Our findings also reveal the following patterns：the mean fertility intention level is 1.86 [ 1.82, 1.88 ], much lower than the replacement level ; Younger cohorts tend to have lower fertility intention, which means the overall intention level is expecting a declining trend; The fertility intention of cohorts at child-bearing age is higher than their lifetime fertility level, and the difference between the two indicators is also larger among younger people. The above messages all cast doubt on the efficacy of the ongoing selective two-child policy.