In Vietnam, all lands belong to the state, who assigns usufruct rights to those lands to individuals and households. In 1993, the state gave 20-year usufruct rights to growers of annual crops, and 50-year usufruct rights to growers of perennial crops. In 2013, as the usufruct rights of growers of annual crops were set to expire, the Vietnamese government passed a law - the Land Law of 2013 - that extended the usufruct rights of all landowners by 50 years. We exploit this largely unanticipated shock to study the effect of the Land Law of 2013 on the investment behaviour of growers of annual crops. Using a difference-in-differences design, we find that the Land Law of 2013 is associated with a higher likelihood of investment in irrigation technology or soil and water conservation, but not other types of investment. Our results are robust to controlling for endogenous switching from annual to perennial crops, and our data support the parallel trends assumption. Our results also suggest that the long-term effects of the Land Law of 2013 are larger than its short-term effects.

中文翻译：

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土地保有权和农业投资：来自越南的证据

在越南，所有土地都属于国家，国家将这些土地的使用权分配给个人和家庭。1993年，国家给予一年生作物种植者20年使用权，多年生作物种植者给予50年使用权。2013 年，随着一年生作物种植者的使用权即将到期，越南政府通过了一项法律——2013 年土地法——将所有土地所有者的使用权延长了 50 年。我们利用这种很大程度上出乎意料的冲击来研究 2013 年土地法对一年生作物种植者投资行为的影响。使用差异中的差异设计，我们发现 2013 年土地法与灌溉技术或水土保持投资的可能性更高有关，但与其他类型的投资无关。我们的结果对于控制从一年生作物到多年生作物的内源性转换是稳健的，我们的数据支持平行趋势假设。我们的结果还表明，2013 年土地法的长期影响大于其短期影响。