So to think about the price of say iron ore today, it might make sense to consider the cost of steel

譬如說，若要探討現今鐵礦的價錢，應先回溯到西元1688年光榮革命時期，

carried by the troops of William and Mary in the Glorious Revolution of 1688.

由威廉國王和瑪麗皇后領軍搬運的鋼鐵價錢。

Or for that matter, the price of French guillotine steel a century later, or the expensive casting canons

另外，還有一個世紀後法國斷頭台所用的鋼鐵價錢，或是俾斯麥將軍在西元1871年

when Bismarck unified the German States in 1871.

統一德國時所用的昂貴大砲。

A little too much perspective perhaps. Focusing on the twentieth century then.

上述可能有點太久遠了。現在來著重在20世紀，

And the price of commodities through a period of industrialization, wars, development, and globalization.

以及工業化、戰爭、發展跟全球化之下的物價。

In that context, the recent experience for commodity prices looks like the third big bubble for raw materials.

從最近的經驗來看，原料商品的價錢面臨第三次泡沫化。

The first peaked early in the 1920s; the second came after the oil shock of the 1970s.

第一次泡沫化發生在西元1920年初期；第二次是在西元1970年代石油危機之後。

And the most recent as China moved a large proportion of its population into cities,

還有最近一次是因為中國將大部份的人口遷徙到城市，

going from a closed economy to the world's second-largest.

並從一個封閉經濟體轉變成為世界第二大經濟體。

As growth in China has begun to slow, well, prices for raw materials have collapsed.

隨著中國的經濟成長逐漸趨緩，原料的價錢隨之崩盤。

You can see this also in our second chart, which shows the relationship between the oil price and inflation over time.

也可以從第二張圖中看出，圖上顯示西元1900年以來油價跟通膨的關係。

It's a logarithmic scale, but as you can see, ultimately the oil price tends to come back to inflation.

這邊用的是對數刻度，但可以觀察到油價逐漸下降回到跟通膨指數相近。

The point of the history lesson is to realize the collapse so far is incomplete.

前車之鑑讓我們了解目前價格崩盤尚未結束。

BCA research have compared a basket of the the commodity prices against consumer prices since 1680.

宏觀投資研究機構比了較西元1680年以來部分商品的價錢跟消費者物價。

And over time, the two did not fundamentally diverge, at least for long.

一段時間之後，兩項指標並沒有發散 — 至少長遠來看沒有。

Demand for what is pulled from the ground has risen dramatically at times.

原料的需求不時的急速上升。

But this merely serves to send geologists looking for more.

但是，這只會讓地質學家去開發更多的原料。

Technology improves as well, as does the productivity of extraction, transportation, and manufacturing.

科技進步促使抽取、運輸、製造的生產力上升。

So a decade when price rises much faster than inflation, well, that caused new mines to be dug, wells sunk and shell to be fractured.

所以當原料價格上升幅度遠比通膨速率大時，促成開挖鐵礦、井水下沉、岩層被破壞等現象。

To bring commodity prices back into line with consumer prices now, well, that's going to require another fall

宏觀投資研究機構預估為了要把原料的價錢拉回來跟消費者物價指數相符，

by as much as forty percent, estimated BCA.

價錢會需要下降至少40%。

In terms of the oil price, think 30 dollars a barrel as a reasonable estimate of what the long run suggests.

至於油價方面，儘管長遠來看一桶原油30美元看似合理，

But also remember, prices can overshoot on the way down as well as the way up.

但也要記住，油價可能會急速下跌也可能急速上升。