Lawrence Person's BattleSwarm Blog

A variety of maladies (global inflation, soaring energy costs due to the Russo-Ukrainian War, and post-Brexit trade wrangles, among others) has the English pound approaching parity with the U.S dollar.

Can the pound reach parity versus the dollar? It’s now a one-in-four chance when it comes to options pricing.

The UK currency is heading for its biggest daily loss since early May after Chancellor of the Exchequer Kwasi Kwarteng outlined the government’s plans to stimulate the economy with tax cuts and spending. The simultaneous sharp sell off in Gilts [historical term for UK government bonds – LP] suggests that tackling inflation will be a very hard task for UK authorities and that the currency market sees no easy way out for the Bank of England.

To attract foreign investors, a weaker pound may be the answer and that is what FX traders are betting on.

Cable fell as much as 2.1% to touch $1.1021, the lowest since March 1985, and was at $1.1036 as of 12:38pm in London. Risk reversals, a barometer of market positioning and sentiment, show that traders see the greatest downside risks for the pound over the medium term in two years.

According to Bloomberg’s options pricing model, the pound holds a 26% chance of touching parity versus the greenback in the next six months. That compares to a reading of 14% Thursday.

I think the real odds are probably higher than that.

Dollar-pound parity is something that’s never happened, with the nearest it came to some 1.05 dollars to the pound in the mid-1980s. But there’s always a first time for everything, and with the Bank of England doing more quantitative easing and the UK government going on a spending spree during soaring inflation while the Fed ratchets up interest rates, now is as good a time as any.

Besides making imports from the UK less expensive, what effects will dollar-pound parity have on the financial world? Hard to say for sure, but my prediction is: Weird things.

There are a variety of reasons for this, starting with the fact that currency trading is itself a weird thing. You may think “American financial houses buy pounds to purchase English goods, while UK financial houses buy dollars to purchase American goods,” but there’s a whole ecology of counter-party trades, hedging strategies, currency reserve requirements, portfolio balancing, and a host of other considerations.

Here’s a brief video that cover some of the basics for how brokerages handle FX trading:

That’s a fairly streamlined view, as it doesn’t cover how liquidity pools are set up, different hedging strategies, etc.

There are even traders who specialize in just trading different duration T-Bills, selling the eight-week-out and buying the four-week-out (or vice versa) for esoteric arbitrage reasons.

None of that will change if the market hits dollar-pound parity. So where’s the danger? That comes from the possible non-linear effects of the market doing something that a lot of algorithmic instrument designers never considered a possibility.

For a simple example, let’s talk about the swaps cases. To summarize a whole lot of very complex cases, a whole bunch of local UK governments entered into interest rate swap agreements. Interest rate swap agreements are a legitimate hedging strategy to minimize exposure to interest rate swings, but a few municipalities saw it as a license to print money. To quote Wikipedia, the source of all vaguely accurate knowledge:

The position of Hammersmith and Fulham London Borough Council was quite different from most of the other local authorities. From about 1985 onwards Hammersmith had entered into interest rate swap transactions on an extremely large scale. At one stage it was calculated that Hammersmith was a counterparty to 0.5% of the global trade in swaps, and 10% of the sterling denominated trade. Moreover, quite exceptionally, all of Hammersmith’s positions in the swap market were betting on a fall in interest rates. Most large participants in the swap market have their exposure balanced by taking positions on both sides and across multiple currencies, but Hammersmith was essentially repeatedly entering into one-way bets that sterling interest rates would fall; a bet that they would end up losing spectacularly when interest rates climbed from around 8 per cent to 15 per cent in the space of ten months.

This was, to put it in technical terms, “a really fucking stupid thing to do.” The swaps cases were unwound with great expense and difficulty, and various English banks ended up taking a bath (which you know they must have regarded as some sort of diabolical violation of the natural order) after courts determined that the authorities in question didn’t have the authority under English law to enter into such agreements.

The possibility that interests rates can rise should be an obvious one. But the idea that the pound might be worth less than the dollar is one that people have probably thought about a good deal less, since it hasn’t happened ever. It’s quite possible it hasn’t been contemplated in some percentage of the trillions in derivatives markets and hedging instruments around the world.

For many financial systems, this is going to be an untested use case. Some systems may work just fine, others may break down, and still others may experience race conditions or cascading failures; think of the flash crash of 2010, or the 1987 Black Monday crash. Somewhere, somehow, something is likely to go off the rails.

Hopefully, whatever does blow up won’t be big enough to take down the entire market, or at least not for long. Hopefully it won’t uncover massive problems like the 2008 subprime meltdown uncovered, and there won’t be a firm of systemic importance like AIG was there.

Hopefully.