When trading interest rates, most people are familiar with instruments such as deposits, FRAs, futures, or swaps. These inputs are directly observable in the market, e.g. via Bloomberg or Reuters feeds.
However, there are instances where rates traders must apply discretion when constructing the yield curve. In such cases, they often estimate certain inputs using statistical or judgment-based approaches. One such input is the concept of "Turns".
What are turns?
Turns represent a trader's view that the anticipated overnight rate on a specific future date, typically at month-end or year-end will be X basis points higher or lower than on regular trading days. There is empirical evidence supporting the existence of turns, as illustrated by historical rate data.Why do Turns exist?
Turns exists due to a variety of factors, which differ from one economy to another. For example, the presence and magnitude of turns may depend on whether the economy is rates-driven (like G5 countries) or FX-driven (such as export-oriented city-states like Singapore or Hong Kong SAR).Take, for example, a chart of the EUR €STR rate (attached). This rate regularly spikes downward toward month ends. In Europe, €STR represents the rate at which a large number of banks are able to lend directly to each other at overnight unsecured rates.

At month ends, unsecured lending is either reduced or shifted toward the secured repo market to improve balance sheets (window dressing). This causes the perceived spikes shown in the chart.
In fact, there is empirical evidence of turns taking opposite sides on secured and unsecured rates (see the attached table).
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Turns on secured and unsecured markets |
What happens if turns are ignored?
IRS trading is the bread and butter of many investment banks. Capital is always tight, and trading spreads are competitive. A cash flow on 31 December 2030 will clearly have a different value than on 1 January 2031. Failure to recognize this when making IRS markets will clearly lead to suboptimal decisions, which will accumulate over time and hurt P&L.Which markets exhibit the most significant turns?
One of the most notorious examples of money markets with turns is the HONIA rate in Hong Kong, where turns regularly print in high double digits.HKD is pegged to USD, and there is strong demand to hold USD for end-of-month reporting purposes by a wide range of market participants. Through the effects of LERS and HKMA operations, this results in the HKD HONIA rate often spiking upwards.
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Hong Kong |
Other markets that experience strong turns are Singapore (SORA), Korea (KOFR), Poland (WIRON), and Mexico (F-TIIE).
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Mexico |
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Poland |