The Rupee

How big is the market for the rupee?
The rupee is now a big market. Summing across both spot and derivatives, perhaps $30 billion a day of onshore trading and $40 billion of offshore trading takes place. Both these markets are tightly linked by arbitrage. In other words, for all practical purposes, it is like National Stock Exchange (NSE) and Bombay Stock Exchange (BSE) which are a single market unified by arbitrage.

If you place a small order to buy 100 shares on either NSE or BSE, you get essentially the same price, and arbitrageurs are constantly at work equalising the price across both markets. It is a similar state of affairs between the onshore and the offshore rupee. Both markets are tightly integrated by arbitrage.

The offshore market for the rupee, and a large part of the onshore market, is Over-the-counter (OTC) trading. Hence, the efficiencies of algorithmic trading and algorithmic arbitrage cannot be brought to bear on onshore/offshore arbitrage. So the arbitrage is done by manual labour. Still, it gets done. Both markets are tightly linked and show the same price. We should think of them as one market- big market, it is one of the big currencies of the world, and it’s roughly $70 billion a day.

Q: How might RBI do manipulation of this market?
If Reserve Bank of India (RBI) wants to hit the market with orders big enough to make a difference, they have to be ready to do fairly big orders and to be able to do it on a sustained basis. As a rough thumb-rule, I might say that in order to make a material difference to a market with daily volume of $70 billion, they have to be in the market with at least $2 to $3 billion a day.

Q: What would go wrong if they tried this?
Three things would go wrong.
First, foreign exchange reserves are $275 billion. If RBI sells off $2.75 billion a day, the reserves would be quickly gone.

Second, when RBI sells dollars and buys rupees, this sucks liquidity out of the market. The side effect of selling dollars would be a sharp rise in domestic interest rates. In other words, monetary policy would get hijacked by currency policy. This would not be wise.

Monetary policy should be focused on delivering low and stable inflation: it should have no ulterior motives. We have to make a choice: Do we want to use up the power of monetary policy to achieve domestic goals, or do we want to use up the power of monetary policy to achieve currency policy goals?

Third, suppose you and I saw a market price of Rs.45 per dollar, which is created by RBI and not a market reality. We would know that in time, the truth will out, that the price will go back to Rs.52 a dollar. The rational trading strategy for each of us would be: To sell any and every domestic asset, and shift money out of the country.

This would trigger off an asset price collapse in India. We would take the money out, and wait for the distortion of the currency market to end. At that point (perhaps Rs.52 a dollar, perhaps worse) we would bring the money back to India and buy back our assets. We might make two returns here: first, on the move of the INR/USD from 45 to 52 (or worse) and the second, on the gain from the drop in asset prices.

Q: Isn’t it hard to take money out of India in this fashion?
It is easier than we think. Remember September 2008? The mythology in our heads was: we in India are crouching safely behind a wall of capital controls. In truth, the wall wasn’t there.

Q: But until recently, RBI used to give us a pegged INR/USD exchange rate! What changed?
In late 2003, RBI ran out of bonds for sterilisation. Associated with that, there was a first structural break in the rupee exchange rate regime, with a doubling of volatility. A short while later, in March 2007, there was another structural break, with another doubling of volatility. From April 2009 onwards, RBI’s trading in the market has gone to roughly zero. RBI stopped managing the exchange rate a while ago.

The exchange rate is the most important price of the economy. The decontrol of this exchange rate is the biggest achievement of the UPA in economic reforms. The credit for this goes to Y. V. Reddy and Rakesh Mohan (who took the first two steps of doubling exchange rate flexibility twice) and to Dr. Subbarao (who got out of trading on the currency market, which did remarkably little to INR/USD volatility).

Q: Why did nobody tell me that something changed in the exchange rate regime?
RBI should be talking more transparently about what is going on. But they are not transparent about what they do. Even though hundreds of millions of people are affected by their trading on the currency market (or the lack thereof), the manual which governs their currency trading at any point in time (i.e., the documentation of the prevailing exchange rate regime) is not transparently disclosed to the people of India. We have to decipher what is going on by statistically analysing exchange rate data.

The dates of the structural break of the exchange rate regime are extremely important dates in thinking about what was going on in macroeconomics and international finance. Any time one is using data about exchange rates, interest rates, etc., it is important to work within one segment of the prevailing exchange rate regime at a time. It is wrong to pool data across many years. All users of data need to be careful in this regard.

Q: So what might happen to the rupee next? Is there a `law of gravity’ which will pull it back to erstwhile values of Rs.45 or Rs.50?
When you don’t manipulate a financial market, the price time-series comes out to something close to a random walk. In the ideal random walk, all changes are permanent. The random walk never forgets; there is no law of gravity which takes it back to recent values. Your best estimator of what it will be tomorrow is: what you see today.

In order to get a sense of what will come next, go through the following steps. First, go to INR/USD options trading at NSE, and pluck out the implied volatility for the four at-the-money options. I just did that, and the values are: 10.43, 10.32, 10.33 and 10.08. Calculate the average of these four numbers. With the above four values, the average is: 10.3. (This is a quick and dirty method; here is one which is much better).

This tells a very important thing: The options market believes that in the future, the volatility of the INR/USD rate will be 10.3 per cent per year.

In order to re-express this as uncertainty per month, we divide by sqrt(12). This gives the volatility for a month as: 3% per month.

Roughly speaking, the 95% confidence interval for what might happen over a month, then, runs from -6% to +6% (this is twice the standard deviation, which we just worked out was 3% per month).

The INR/USD is now Rs.51.62. By the above calculation, we can be 95% certain that one month from today, it will lie somewhere between 48.5 and 54.7.

These trivial calculations have been done by equity market participants for the longest time. It is a standard and trivial idea: To read the implied volatility off the Nifty options market and to do such calculations to get a sense of what might come next with Nifty. But on the currency market, this is relatively novel.

Only recently have we got a nice currency options market, and only recently have we got to a genuine market. Now these skills can be brought to bear on the currency market. It’s a brave new world, one in which the operations of financial derivatives markets (Nifty options, INR/USD options) produces forward-looking and timely information about the economy (implied volatility).

Q: What changed in imports and exports which gave us the big recent move of the rupee?
The current account (goods, services, and then some) adds up to a mere buying and selling of $4 billion a day. The bulk of currency trading is about the capital account. The currency is a financial object; the exchange rate is defined by financial considerations and not by current account considerations.

Q: What happens to the Indian economy when the rupee depreciates?
This has been the source of a great deal of confusion and it’s important to think straight about this. There are three important effects in play:

1. Some people had borrowed in dollars, and left it unhedged since they were speculating that the INR would appreciate. They have got burned. That’s okay – in a market economy, many people place bets about future fluctuations of financial prices, and half the time the speculator loses money. (If the rupee had not depreciated sharply, these speculators would have been truly joyous).
   
2. When the rupee depreciates, imports become costlier and India’s exports become more competitive. So exports (X) gradually start going up and imports (M) gradually start going down. The net gain in X-M is increased demand in the local economy. In this fashion, INR depreciation is good for aggregate demand (and conversely INR appreciation pulls back demand). However, we have to bear in mind that these effects are small and take place with long lags.
   
3. Many things in India are trade-able. It is important to focus on the things that are trade-able and not just on the things that are imported. As an example, there are many transactions between a domestic producer of steel and a domestic buyer of steel. The buyer and seller are both in India. But the price at which they transact is the world price of steel (which is quoted in dollars) multiplied by the INR/USD exchange rate. This situation is called `import parity pricing’. Through this, the domestic price of trade-ables goes up when the rupee depreciates.
   

Q: What is the impact of costlier trade-ables for RBI?

RBI’s job is to fight inflation. RBI must work to deliver year-on-year CPI inflation (a.k.a. `headline inflation’) of four to five per cent. When trade-ables become costlier, domestic CPI inflation goes up. So the rupee depreciation has made RBI’s job harder.

RBI will have to respond by hiking interest rates. (Note that one impact of higher interest rates will be that more capital will come into India, which will tend to yield a rupee appreciation; import parity pricing has created a new channel through which RBI rate hikes combat inflation).

Q: What is the impact of costlier trade-ables for business cycle conditions in India?

As the example above about steel suggests, the price realisation of all trade-ables companies goes up when the rupee depreciates. Costs change by less by revenues (since many costs are not trade-ables), and profitability goes up.

Firm profitability has dropped sharply in 2011. My prediction is that firms producing trade-ables will show better profitability in Oct-Nov-Dec 2011 when compared with the previous quarter, thanks to the rupee depreciation.

This is great news for business cycle conditions. Profitability goes up, which yields more cash for investment by financially constrained firms. And, when profitability is higher, more investment projects look viable.

Q: In the bottom line, what is the link between the rupee and India’s business cycle stabilisation?

If RBI tried to peg the exchange rate, the lever of monetary policy would get used up to deliver the target exchange rate. By not trading on the currency market, the lever of monetary policy is now available.

A pretty good use for this lever is to deliver low and stable CPI inflation. If this is done, then an RBI focused on inflation would help stabilise the economy by cutting rates when CPI inflation drops below 4% and hiking rates when CPI inflation goes above 5%.

But floating the exchange rate also yields stabilisation purely in and of itself. In bad times, capital leaves India, the rupee depreciates. This gives higher profitability in trade-ables firms and bolsters investment. Conversely, when times are good, more capital comes into India, the INR appreciates, which crimps profitability of trade-ables firms.

The floating exchange rate exerts a stabilising influence upon the economy: purely by doing nothing on the currency market, RBI has unleashed this new force of stabilisation which will help India.

Q: What should RBI do next?

RBI should do as they have done, i.e. avoided trading on the currency market. RBI should keep driving up the short-term interest rate until point-on-point seasonally adjusted CPI inflation shows a decline and goes into the target zone of 4-5 per cent. After this hangs in there for a year, `headline inflation’ (y-o-y growth of CPI) will be in the target zone.

Q: What do other countries do?
When we look at countries with good governance, the mainstream strategy seen worldwide is an open capital account and a central bank that delivers on an inflation target. By and large, this goes with a floating exchange rate. Trading on the currency market interferes with achieving price stability and has hence been dispensed with, by most good countries. Japan and Switzerland come to mind as exceptions to this broad regularity.

Note: This post originally appeared here