????在這幅圖中，各國之間的差距小了很多。實際上，美國甚至不再是第一名。按人均值計算，這些國家的經濟增長率分別為：

????? 英國2.0%

????? 美國1.8%

????? 日本1.6%

????? 法國1.2%

????如果不考慮較快的人口增長，美國和同類富裕國家在經濟增長方面的差異就會少很多。這讓我們看清楚了一些問題，比如當下對美國醫療改革的探討。英國有社會化醫療，它讓政府支出占年度GDP的比重提高到近50%；在這種情況下，英國的人均GDP增長速度還超過了美國，而后者的政府開支在GDP中所占的比例較小。

????所以說，人口增長有利于經濟發展。這似乎顯而易見——更多的人口意味著更多的經濟活動。在美國，人口增長越來越依賴于移民。當然，美國的人口出生率高于其他富裕國家，但這個數字正在下降。美國人口普查局（Census Bureau）估算，移民將是今后30年美國人口增長的主要動力。

????目前人們正在討論財富和收入差距不斷拉大的現象，引發這場討論的很大一部分數據都由法國經濟學家托馬斯?皮凱蒂負責整理。皮凱蒂在他即將出版的新書《21世紀的資本》（Capital in the 21st Century）中談到了這個問題。他指出，在美國歷史上，私人財富在很長一段時間里都沒有像歐洲那樣不平均地高度聚集起來，其中的主要原因就是移民。皮凱蒂寫道：

????（移民）是美國對全球再分配做出的巨大貢獻：獨立戰爭期間，美國的人口數量幾乎不到300萬，現在增長到了3億多，主要得歸功于連續不斷的移民浪潮。這就是為什么美國還遠遠不會成為新的老式歐洲……移民像灰漿一樣把美國砌成了一個整體；他們具有穩定作用，讓越來越大的勞動收入差距在政治和社會層面變得可以忍受……在收入水平處于后一半的美國人中，相當多的人認為收入不均是第二重要的事情，原因僅僅是他們出生在一個不太富裕的國家，而且認為自己的人生軌跡正在上升。

????換句話說，移民不僅促進經濟增長，它還防止財富的集中在整個發達世界引發政治不穩定局面。人口增長沒有降低有錢人的富裕程度，但它確實削弱了財富的力量。和人口與經濟都在增長的國家相比，以及人口和經濟都處于滑坡狀態的國家，一百萬美元的價值要高得多。（財富中文網）

????譯者：Charlie

????

????Here, the competition is much closer. In fact, the U.S. doesn't even win. On a per capita basis, these countries grow at:

????? 2.0% in the U.K.

????? 1.8% in the U.S.

????? 1.6% in Japan

????? and 1.2% in France.

????Take away America's faster population growth, and there's a lot less of a difference between its economic growth compared to its wealthy nation peers. This puts into perspective, for instance, the current debate over health care reform in the U.S. Britain has socialized medicine, a fact that pushes the share of yearly GDP spent by the government close to 50%, yet it has managed to grow its economy faster than the U.S. on a per-capita basis, for which government spending represents a smaller share of GDP.

????So, population growth is good for economic growth. This seems intuitive -- more people means more economic activity. And in the U.S., population growth is increasingly reliant on immigration. Sure, birth rates are higher in the U.S. than in other wealthy countries, but they are on the decline, and the Census bureau estimates that immigration will be the main driver of population growth within 30 years.

????Thomas Piketty, the French economist responsible for compiling much of the data driving today's debate over growing wealth and income inequality, raises this issue in his forthcoming book, Capital in the 21st Century. He points out that immigration is also the primary reason the U.S. has, for much of its history, avoided the large and unequal concentrations of private wealth that developed in Europe. He writes:

????[Immigration] was the great contribution of the United States to global redistribution: the country grew from a population of barely 3 million at the time of the Revolutionary War to more than 300 million, largely thanks to successive waves of immigration. That is why the United States is still a long way from becoming the new Old Europe ... immigration is the mortar that holds the United States together, the stabilizing force that makes increasingly large inequalities of labor income politically and socially bearable ... for a fair proportion of Americans in the in the bottom 50 percent of income, these inequalities are of secondary importance for the very simple reason that they were born in a less wealthy country and see themselves as being on an upward trajectory.

????In other words, not only does immigration boost growth, it also combats the kind of concentration of wealth that has fueled political unrest across the developed world. Population growth doesn't make the rich any poorer, but it does diminish the power of wealth. A million dollars is going to be a much more valuable thing to have in a country in which the population and economy are shrinking than in a country where the population and economy are growing.