Setting prices crudely
Few had heard of Libor until London's inter-bank lending rate went through the roof in 2008 - the key measure of the stress in the financial system and the mistrust banks felt for each other.
But it only became widely known when it was confirmed this summer that bankers had been manipulating it, both to hide their own institutional weakness and to make bigger profits for traders.
Many of us have been astounded to find that a handful of people in the City of London have had control - without oversight - of "the most important number in finance", which is the reference point for at least $300 trillion of financial instruments.
That's quite a big number, so let's give it full vent: $300,000,000,000,000. Libor may have an impact on even more than that, but once you've passed your three hundredth trillion, you've probably stopped counting.
Today, we have a plan for setting it independently, reliably, with oversight and with criminal sanctions for those who seek to manipulate it.
This morning's speech by Martin Wheatley, soon to become boss of the Financial Conduct Authority, also points out that Libor is not alone in being both powerful and barely unregulated. And he suggests that others might pay heed to what went wrong with Libor.
There's the range of FTSE numbers, for instance, which are a reference point for a lot of contracts. There's gold and other metals. And the risk of manipulation of food commodity prices has a big impact on a lot of people, some of them very vulnerable to fluctuations.
Then there's oil, and after the wild fluctuations in 2008, the setting of the price per barrel also came under scrutiny. The market prices affect tax, royalties and profits, and have a huge bearing on oil companies' investment decisions.
While such market information is something you can easily find for free, getting reliable data and analysis is big business. Just ask Wood Mackenzie, the Scottish-based energy information company, which yesterday announced strong growth last year, to reach profits of £71m.
For all those trading oil from minute to minute, they need reliable information on what's happening in the market.
And they rely on a handful of private companies, dominated by Platts. It's American, 103 years old, part of McGraw-Hill and it insists on forcing those reporting prices to do so on its terms. Each of these Price Reporting Agencies has a different methodology, to provide them with that information.
Dominated by the benchmark price of Brent crude, the black stuff that flowed from what was once the North Sea's biggest-producing field, the work of these PRAs has been looked at in some technical detail by the International Organisation of Securities Commissions (IOSCO).
It's looked not only at Brent crude but at some other exotic hydrocarbon cocktails - West Texas Intermediate, the Argus Sour Crude Index, Brent Blend or BFOE (the basket of the North Sea's Brent, Forties, Oseberg and Ekofisk), Dubai and Oman, Tapis and Minas, and East Siberia-Pacific Ocean Blend.
And while they say there can be significant variations in some of these, it seems one of the reasons Brent crude continues to appeal is that there's least variation in its price, at around one US cent per barrel over a long period.
However, IOSCO noted: "On any given day, the differences in prices reported by different PRAs for the same crude oil grade can be substantial, even when allowance is made for the different delivery periods considered."
Reporters of oil prices are relied upon to use their judgement and experience to assess whether traders might be misleading them. Compiling a report for G20 finance ministers last year, IOSCO found those other players in the market want regulation, but doubt financial regulators have the expertise to provide it.
And it's noted the main PRAs have no independent auditing, or complaints procedure to protect against conflict of interest.
"There is no contractual, legal or regulatory requirement to report transactions to PRAs. It is therefore open to companies to report only those deals that are in their own best interests for the rest of the market to see."
And "the deal evidence on which PRAs assess benchmark prices is only a tiny fraction of the global petroleum trade."
So while there's no evidence of manipulation of some of the other important benchmarks, this summer brought forward proposals to bring them into line with the revamped and more reliable Libor.
Platts and three other leading PRAs have said they still believe in self-regulation, but recognise a code of conduct will be required.
The proposals suggest that will involve clear rules on reliable methodology, how judgement is applied to using information, transparency about submitted information, a complaints procedure and external oversight.
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