正文
The share of households aged under 30 who own their own home has fallen from one in five in 1997 to one in eight. On July 24th Sir Keir Starmer, the new prime minister, said that Britain’s failure to build was denying young people ”the basic dream of homeownership”.
30岁以下家庭拥有自己住房的比例，也从1997年的五分之一下降到如今的八分之一。7月24日，新任首相凯尔·斯塔默爵士指出，英国在住房建设上的失败剥夺了年轻人“拥有住房的基本梦想”。
His party has promised 1.5m new homes in England over
this parliament to alleviate the housing crisis. That would represent a 27%
increase in the number of new homes built over the past five years. It is a
target that has not been hit in decades. But assume, for argument’s sake, that
it is met. Would that make housing more affordable?
他的政党在本届议会上已承诺将在英格兰新建150万套住房，以期缓解当前严峻的住房危机。这一举措意味着，与过去五年相比，新建房屋的数量将增加27%，这是一个几十年来从未达到过的目标。然而，即便这一目标得以实现，我们仍需探讨，这是否真的能让房价变得更便宜？
Economics 101 says that the price of a product moves
inversely to its availability. If the country builds more homes, all things
being equal, house prices should fall.
经济学的基本原理告诉我们，产品的价格与其可得性成反比。因此，如果国家建造更多的房屋，在其他条件保持不变的情况下，房价理应会下跌。
But housing is more than just a product. It is also an asset whose price, much like a share or a bond, is a function of the discounted net present value of cashflows—ie, rental income—from that home. Prices are heavily affected by changes in interest rates, not just by the number of homes that are built.
但住房不仅仅是一种产品，它也是一种资产。其价格机制与股票或债券相似，是现金流（即房屋租金收入）贴现净现值的函数。这意味着，房价不仅受到新建房屋数量的影响，还受到利率变化的严重影响。
In the decade to 2010, for instance, the housing stock
in England rose by 8% but real house prices soared by 70% as the cost of debt
fell. Over the past year house prices have fallen moderately in response to
high mortgage costs.
例如，在截至2010年的十年间，英格兰的住房存量上涨了8%，但随着债务成本的下降，实际房价却飙升了70%。而在过去的一年里，由于抵押贷款成本高企，房价出现了适度的下跌。
A study by the Bank of England (BoE) in 2019 using an asset-price model found that about half of the 170% rise in real house prices between 1985 and 2018 can be explained by falling real interest rates, and the rest by rising incomes.
英国央行在2019年使用资产价格模型进行的一项研究发现，1985年至2018年间，实际房价上涨了170%。其中，约有一半的涨幅可以用实际利率的下降来解释，而其余一半则可以用收入的增加来解释。
