At one point in the morning yesterday, oil was trading as low as $25.25 a barrel.

Crude oil traded at $26.36 the day of the 2002 summit meeting, about half the current price.

During the day, oil traded from $34 to $36.95 a barrel.

Crude oil has recently been trading at more than $30 a barrel.

That's high, when you consider that oil mostly traded between $15 and $25 for the past generation.

And if oil is then trading at $18.60, the buyer would break even, minus the opportunity costs of tying up money for five years.

The vouchers allowed them to profit by selling the oil or the right to trade it.

Five years ago, oil traded for $11.30 a barrel.

That is not possible now, because oil did not trade freely before 1973.

At the market's peak, in October, oil traded above $40 a barrel.