---
ticker: "KRMSB"
title: "South Korea Monetary Stabilization Bond 91-Day Yield"
unit: "%"
frequency: "Daily"
source: "Macaulay (1938); Nelson and Siegel (1987)"
release: "Updated Daily"
category: "Interest Rates"
country: "KR"
language: "en"
canonical: "https://kred.dev/en/series/KRMSB"
license: "https://creativecommons.org/licenses/by-nc-nd/4.0/"
latest_value: 3.16
latest_date: "2026-10-08"
first_date: "2006-09-25"
observations_total: 4958
observations_shown: 120
---

# South Korea Monetary Stabilization Bond 91-Day Yield

## Overview

The three-month liquidity-absorbing security yield reflecting open-market operation conditions.

## Key Figures

|  | Value | Date |
|---|---|---|
| Latest | 3.16 | 2026-10-08 |
| Change from previous | 0.00 | 2026-10-07 |
| Change over one year | +0.80 | 2025-10-02 |
| Highest on record | 5.43 | 2008-08-18 |
| Lowest on record | 0.47 | 2021-05-21 |
| Period covered | 2006-09-25 – 2026-10-08 |  |
| Observations | 4958 |  |

## Recent observations

| Date | Value | Change |
|---|---|---|
| 2026-04-13 | 2.54 | -0.01 |
| 2026-04-14 | 2.53 | -0.01 |
| 2026-04-15 | 2.53 | 0.00 |
| 2026-04-16 | 2.54 | +0.01 |
| 2026-04-17 | 2.56 | +0.02 |
| 2026-04-20 | 2.55 | 0.00 |
| 2026-04-21 | 2.55 | 0.00 |
| 2026-04-22 | 2.56 | +0.01 |
| 2026-04-23 | 2.58 | +0.02 |
| 2026-04-24 | 2.59 | 0.00 |
| 2026-04-27 | 2.54 | -0.05 |
| 2026-04-28 | 2.55 | +0.01 |
| 2026-04-29 | 2.55 | 0.00 |
| 2026-04-30 | 2.56 | +0.01 |
| 2026-05-04 | 2.57 | 0.00 |
| 2026-05-06 | 2.57 | 0.00 |
| 2026-05-07 | 2.56 | -0.01 |
| 2026-05-08 | 2.56 | +0.01 |
| 2026-05-11 | 2.57 | +0.01 |
| 2026-05-12 | 2.59 | +0.02 |
| 2026-05-13 | 2.58 | -0.01 |
| 2026-05-14 | 2.59 | 0.00 |
| 2026-05-15 | 2.61 | +0.02 |
| 2026-05-18 | 2.61 | 0.00 |
| 2026-05-19 | 2.61 | 0.00 |
| 2026-05-20 | 2.61 | 0.00 |
| 2026-05-21 | 2.61 | 0.00 |
| 2026-05-22 | 2.60 | 0.00 |
| 2026-05-26 | 2.60 | -0.01 |
| 2026-05-27 | 2.62 | +0.02 |
| 2026-05-28 | 2.63 | +0.01 |
| 2026-05-29 | 2.62 | 0.00 |
| 2026-06-01 | 2.64 | +0.02 |
| 2026-06-02 | 2.64 | 0.00 |
| 2026-06-04 | 2.66 | +0.02 |
| 2026-06-05 | 2.67 | 0.00 |
| 2026-06-08 | 2.69 | +0.02 |
| 2026-06-09 | 2.67 | -0.02 |
| 2026-06-10 | 2.67 | 0.00 |
| 2026-06-11 | 2.67 | 0.00 |
| 2026-06-12 | 2.66 | -0.02 |
| 2026-06-15 | 2.65 | 0.00 |
| 2026-06-16 | 2.65 | 0.00 |
| 2026-06-17 | 2.65 | 0.00 |
| 2026-06-18 | 2.66 | +0.01 |
| 2026-06-19 | 2.66 | +0.01 |
| 2026-06-22 | 2.67 | +0.01 |
| 2026-06-23 | 2.67 | 0.00 |
| 2026-06-24 | 2.68 | +0.01 |
| 2026-06-25 | 2.67 | 0.00 |
| 2026-06-26 | 2.67 | -0.01 |
| 2026-06-29 | 2.67 | +0.01 |
| 2026-06-30 | 2.67 | 0.00 |
| 2026-07-01 | 2.69 | +0.02 |
| 2026-07-02 | 2.69 | 0.00 |
| 2026-07-03 | 2.70 | +0.01 |
| 2026-07-06 | 2.70 | +0.01 |
| 2026-07-07 | 2.71 | +0.01 |
| 2026-07-08 | 2.71 | 0.00 |
| 2026-07-09 | 2.71 | 0.00 |
| 2026-07-10 | 2.72 | +0.01 |
| 2026-07-13 | 2.71 | -0.01 |
| 2026-07-14 | 2.73 | +0.02 |
| 2026-07-15 | 2.73 | 0.00 |
| 2026-07-16 | 2.73 | 0.00 |
| 2026-07-20 | 2.73 | 0.00 |
| 2026-07-21 | 2.74 | +0.01 |
| 2026-07-22 | 2.75 | +0.01 |
| 2026-07-23 | 2.75 | 0.00 |
| 2026-07-24 | 2.76 | +0.01 |
| 2026-07-27 | 2.74 | -0.01 |
| 2026-07-28 | 2.75 | 0.00 |
| 2026-07-29 | 2.75 | 0.00 |
| 2026-07-30 | 2.76 | +0.01 |
| 2026-07-31 | 2.77 | +0.01 |
| 2026-08-03 | 2.78 | +0.01 |
| 2026-08-04 | 2.78 | 0.00 |
| 2026-08-05 | 2.77 | 0.00 |
| 2026-08-06 | 2.79 | +0.01 |
| 2026-08-07 | 2.79 | 0.00 |
| 2026-08-10 | 2.79 | 0.00 |
| 2026-08-11 | 2.80 | 0.00 |
| 2026-08-12 | 2.80 | 0.00 |
| 2026-08-13 | 2.80 | 0.00 |
| 2026-08-14 | 2.74 | -0.06 |
| 2026-08-18 | 2.77 | +0.03 |
| 2026-08-19 | 2.79 | +0.02 |
| 2026-08-20 | 2.81 | +0.02 |
| 2026-08-21 | 2.81 | 0.00 |
| 2026-08-24 | 2.92 | +0.11 |
| 2026-08-25 | 2.92 | -0.01 |
| 2026-08-26 | 2.90 | -0.01 |
| 2026-08-27 | 2.88 | -0.02 |
| 2026-08-28 | 2.98 | +0.10 |
| 2026-08-31 | 3.01 | +0.03 |
| 2026-09-01 | 3.02 | +0.01 |
| 2026-09-02 | 3.02 | 0.00 |
| 2026-09-03 | 3.02 | -0.01 |
| 2026-09-04 | 3.02 | 0.00 |
| 2026-09-07 | 3.02 | 0.00 |
| 2026-09-08 | 3.02 | 0.00 |
| 2026-09-09 | 3.03 | +0.01 |
| 2026-09-10 | 3.04 | +0.01 |
| 2026-09-11 | 3.05 | +0.02 |
| 2026-09-14 | 3.06 | +0.01 |
| 2026-09-15 | 3.07 | +0.01 |
| 2026-09-16 | 3.07 | -0.01 |
| 2026-09-17 | 3.08 | +0.02 |
| 2026-09-18 | 3.10 | +0.02 |
| 2026-09-21 | 3.09 | 0.00 |
| 2026-09-22 | 3.09 | 0.00 |
| 2026-09-23 | 3.09 | 0.00 |
| 2026-09-28 | 3.13 | +0.04 |
| 2026-09-29 | 3.13 | 0.00 |
| 2026-09-30 | 3.14 | 0.00 |
| 2026-10-01 | 3.14 | 0.00 |
| 2026-10-02 | 3.16 | +0.02 |
| 2026-10-06 | 3.16 | 0.00 |
| 2026-10-07 | 3.16 | 0.00 |
| 2026-10-08 | 3.16 | 0.00 |

## Definition

KRMSB is the raw yield-to-maturity on a 91-day monetary stabilization bond recorded exactly as observed without any transformation, and the figure is the per-annum return an investor earns by holding this short-dated liquidity-absorbing security to its three-month redemption. The yield-to-maturity is the single discount rate that equates the security's price to the present value of its redemption proceeds (Macaulay 1938). Because a 91-day instrument carries no intervening coupon, its quoted yield coincides with the three-month zero-coupon spot rate in the discount-function sense (McCulloch 1971, 1975).

This figure sits at the very short end of the term structure (Hicks 1939). Its level is governed jointly by the level factor and by the operating-target rate that a monetary authority pins through open-market operations (Nelson and Siegel 1987; Bindseil 2004; Borio 1997). It also tracks closely the unsecured overnight rate and the secured collateralized repo rate, so the recorded 91-day figure is a near-money-market yield rather than a long-horizon rate (Hamilton 1996; Bartolini, Bertola, and Prati 2002; Duffie 1996).

It is therefore a directly measured short-maturity government-type yield observed daily, the primitive observation that KRED stores rather than a fitted or smoothed construct (Gürkaynak, Sack, and Wright 2007).

## Methodology

KRED applies no transformation to KRMSB and stores the quoted yield daily exactly as observed, so the methodology is limited to the measurement basis by which such a number comes to exist. The yield is the internal rate of return that discounts the bond's redemption value back to its market price (Macaulay 1938). For a 91-day discount security this collapses to a single point on the zero-coupon discount-function curve recovered from coupon-bond prices, and that recovery follows a cubic-spline construction and its tax-adjusted refinement (McCulloch 1971, 1975).

The continuous discount curve from which a clean short-maturity yield is read can be fitted equivalently by several methods. Examples include the exponential-spline method, the parsimonious level-slope-curvature form, and its two-hump extension (Vasicek and Fong 1982; Nelson and Siegel 1987; Svensson 1994). These alternative constructions deliver closely comparable zero-coupon estimates over short maturities (Bliss 1997).

The operational daily procedure of reading par, zero, and forward rates of any maturity from smoothed off-the-run prices follows established curve-fitting practice (Gürkaynak, Sack, and Wright 2007). Its theoretical basis lies in the use of the full term structure of zero rates and in the forward-rate decomposition that links the three-month point to expected future short rates (Fisher and Weil 1971; Hicks 1939). KRED performs none of these steps, and it applies no rescaling, deflating, smoothing, or annualizing, recording the already-measured yield without re-estimation.

## Applications in Economics

The 91-day monetary stabilization bond yield is read economically as the cost of the liquidity-absorbing leg of monetary operations and as a short-end money-market benchmark. Such a short-dated central liability is the sterilization instrument through which excess reserves are drained, so its yield reveals the marginal price the authority pays to keep the overnight rate near its target (Bindseil 2004; Borio 1997). This is the mechanism that steers the overnight rate toward target, and it reflects the liquidity effect and reserve-maintenance mechanics (Bartolini, Bertola, and Prati 2002; Hamilton 1996).

This figure sits one step out from the unsecured overnight rate and the secured repo rate (Furfine 1999; Duffie 1996). The spread of the 91-day yield over those overnight rates therefore captures near-term expectations of policy moves under the expectations-and-liquidity-premium logic (Hicks 1939).

Movements in this short-end level factor summarize the stance of policy and feed the daily short-rate expectations embedded in the broader curve (Nelson and Siegel 1987; Gürkaynak, Sack, and Wright 2007). The historical co-movement of such money-market yields with the business cycle traces back to a long measurement record (Macaulay 1938).

## Applications in Financial Markets

For market participants the 91-day yield is a discounting and valuation building block at the front end of the curve. Because the quoted yield on a near-zero-coupon short bill is the three-month spot rate, it prices and discounts short cash flows directly (McCulloch 1971, 1975). When a full curve is fitted and compared, this figure anchors the short node (Nelson and Siegel 1987; Svensson 1994; Vasicek and Fong 1982; Bliss 1997).

Interest-rate risk on short positions is managed through the duration concept and term-structure immunization, both of which require an accurately observed short yield (Macaulay 1938; Fisher and Weil 1971).

The figure also serves as a funding and collateral benchmark. Because repo specialness and the overnight-funding microstructure govern the cost of carrying a position, desks hedge near-term rate exposure using forward rates of any maturity computed from the curve together with the forward decomposition (Duffie 1996; Furfine 1999; Gürkaynak, Sack, and Wright 2007; Hicks 1939). As such it is a component of money-market valuation rather than a standalone signal.

## Statistical Tests

On the 4,877 daily observations spanning 2006-09-25 to 2026-06-10, fit with a constant and trend, the unit-root battery agrees that the monetary-stabilization-bond yield is integrated of order one. The augmented Dickey-Fuller test of Dickey and Fuller (1979), in the ARMA-consistent lag-augmented form of Said and Dickey (1984) and with lag length set as in Ng and Perron (2001), does not reject a unit root with p = 0.4674, the nonparametric Phillips and Perron (1988) test concurs with p = 0.8828, and the Kwiatkowski et al. (1992) stationarity test rejects its trend-stationary null at p < 0.01, so the verdict is an unambiguous I(1). The GLS-detrended power escalation of Elliott, Rothenberg, and Stock (1996) is reserved for ambiguous outcomes under the house protocol and is not required on this clean reading.

Because the level is integrated, the mean-shift and serial-correlation diagnostics are run on the first difference, the stationary object those procedures require, since a break search or a portmanteau on an integrated level would spuriously segment and read near-unit autocorrelations (Bai and Perron 1998; Perron 1989). The multiple-break procedure of Bai and Perron (1998), computed by the dynamic-programming algorithm of Bai and Perron (2003), finds 2 breaks in the mean of the differenced series, at 2020-06-03, 2023-05-31, read as parameter instability in the sense of Andrews (1993). The Ljung and Box (1978) portmanteau statistic, refining the original Box and Pierce (1970) form, is computed on the first difference and rejects the white-noise null at lags 10 and 20, with Q = 635.59 and Q = 1126.92 and p = 0.000 and p = 0.000, and the automatic portmanteau test of Escanciano and Lobato (2009) concurs with a statistic of 130.47 at p = 0.000.

The series is daily and has no low-integer seasonal period, so the seasonal-unit-root machinery of Hylleberg et al. (1990) and the Canova and Hansen (1995) seasonal-stationarity test are inapplicable and are deliberately not run, the degeneracy of the seasonal auxiliary regression at a daily period being the standard ground (Beaulieu and Miron 1992; Ghysels and Osborn 2001).

## Frequently Asked Questions

### Which rates belong to the short-term money market panel?

The policy rate together with the short-term money market rates closest to its transmission, including the unsecured overnight call rate, the certificate of deposit rate and short-term bank funding benchmarks.

### Why watch money market rates when the policy rate is published?

The policy rate is the instrument; transmission first shows up in money market rates. A widening spread between them is direct evidence of friction in the transmission channel.

### What processing is applied to the base rate and the call rate?

None. Each rate is carried as published, with no seasonal adjustment, smoothing or rebasing.