無論身處什么年代，窮困都不是好事，但一項衡量貧窮的指標(biāo)顯示，2015年對窮人來說是最好的一年。

美國勞工部人口普查局本月稍早發(fā)布的數(shù)據(jù)顯示，2015美國的貧困率下降1.2個百分點(diǎn)至13.5%，貧困人口數(shù)為4310萬，較2014年減少350萬。這是2009年以來貧困率最大降幅。

貧困率下降的主要原因為失業(yè)率降低，最貧窮的美國勞動者薪資隨之上漲。此外，許多州和地方政府近來上調(diào)了最低工資，不少大型私人企業(yè)也自發(fā)提高了工資下限，貧困人群因此受益。

最近，美國聯(lián)邦和地方政府對國內(nèi)貧困問題的嚴(yán)重性格外關(guān)注。因為自林登·約翰遜總統(tǒng)呼吁消除貧困以來已半個世紀(jì)，然而官方數(shù)據(jù)顯示貧困率水平?jīng)]什么變化。

而人口普查局計入殘障社會保障和醫(yī)療補(bǔ)助等政府項目影響的附加貧困指標(biāo)顯示，美國不僅去年貧困率下降，而且由于國家福利舉措更得力貧困率呈穩(wěn)步下滑趨勢。

可是，討論兩種貧困的衡量指標(biāo)時人們往往忽略了一點(diǎn)，無論采用哪種指標(biāo)，貧困的定義都是隨時代發(fā)展不斷變化的。人口普查局計算附加貧困線的方法是，衡量美國家庭通常的消費(fèi)總合，包括“衣、食、住、水電以及小部分滿足其他需求（例如家居用品、個人護(hù)理、工作以外交通）的額外”支出。假如家庭消費(fèi)水平低于美國家庭消費(fèi)中位值的33%，就會被認(rèn)定貧困。

對戰(zhàn)勝貧困抱有希望的人來說，這種統(tǒng)計方法是令人失望的。假設(shè)明天所有美國人都比今天富有50%，支出水平隨之調(diào)整，人口普查局統(tǒng)計出的貧困率并不會變化，因為貧困線只參看家庭消費(fèi)中位值。

所以，一定程度上也要看相對統(tǒng)計數(shù)據(jù)。貧困并沒有絕對確定的定義，美國人對貧困的定義就是不斷改變。擁護(hù)小政府的人感到沮喪很正常，因為這種衡量貧困的方法可能意味著，人類永遠(yuǎn)無法徹底消除貧困，而且政府總能利用統(tǒng)計結(jié)果證明增加支出是合理的。（財富中文網(wǎng)）

翻譯：Pessy

審校：夏林

It’s never a good time to be poor, but 2015 was one of the best in recent memory according to one measure.

According to data released by the Census Department earlier this month, the official poverty rate in America declined by 1.2% to 13.5%, with 43.1 million people in poverty, 3.5 million fewer than in 2014. That’s the largest decrease in the poverty rate since 2009.

The main driver of this phenomenon was the falling unemployment rate, which helped push up wages for the poorest working Americans. That segment of the population was also helped by the fact that many state and local governments have increased their minimum wages of late, while many large private employers voluntarily lifted wage floors as well.

The extent of the poverty problem in the United States has received particular scrutiny of late both because it’s been just over 50 years since President Lyndon Johnson launched the war on poverty, and because during that time the official poverty rate has remained relatively flat.

But the Census Bureau’s supplemental measure of poverty, which takes into account the effect of government transfer programs, like Social Security Disability and Medicaid, shows that not only did poverty fall in the United States last year, it’s been on the steady decline as the welfare state has been strengthened over time.

But what is lost when discussing both these measures of poverty, is that the definition of poverty changes over time, regardless of which you use. The Census Bureau calculates the supplemental poverty threshold by measuring the typical American family’s bundle of consumption on “food, clothing, shelter, and utilities, and a small additional amount to allow for other needs (e.g., household supplies, personal care, nonwork-related transportation). Families that cannot afford the consumption bundle that is at 33% of the median American’s consumption bundle are considered impoverished.

This is a frustrating for those hope the war on poverty can at some point be won. Take for instance a scenario where everyone in the United States got 50% richer tomorrow, and adjusted their spending accordingly. The Census’ measure of poverty would not change, since it’s poverty threshold is relative to the median family’s consumption

It’s understandable why we have to in part rely on relative statistics. There is no absolute definition of poverty—Americans definition of it is bound to change over time. But for devotees of small government, it is understandably frustrating that this strategy for measuring poverty likely means that poverty will never be conquered, and that these measurements can always be used to justify more government expenditure.