Table of Contents
This service uses statistical data published by the Bank of Japan, but the content of this service is not guaranteed by the Bank of Japan.
This service uses statistical data published by the Bank of Japan, but the content of this service is not guaranteed by the Bank of Japan.
The BOJ reported a monetary base of ¥575.8 trillion for May 2026, a decline of ¥7.1 trillion from April (¥582.9 trillion), corresponding to a month-on-month change of -1.2%. Year-on-year the decline was -12.2%, maintaining double-digit contraction. According to BOJ statistics, the year-on-year negative rate has widened stepwise from -9.5% in January 2026, indicating that quantitative tightening within the BOJ's policy normalization process is proceeding steadily.
Looking at the past 12 months, the monetary base fell by ¥13.6 trillion from ¥589.4 trillion in January 2026 to ¥575.8 trillion in May. On a monthly basis it contracted to ¥580.9 trillion in February and ¥570.8 trillion in March, then temporarily rose to ¥582.9 trillion in April before reverting to decline in May. The year-on-year contraction rates were -9.5% (Jan), -10.6% (Feb), -11.6% (Mar), -11.3% (Apr), and -12.2% (May). After peaking in March, the pace of contraction narrowed slightly in April, but widened again in May.
This movement reflects the BOJ's continued implementation of an exit strategy from its quantitative and qualitative easing framework. The decline in the monetary base appears to be driven mainly by a reduction in BOJ current account balances, confirming a gradual compression of banks' excess reserves.
The uncollateralized overnight call rate stood at 0.727%, unchanged from the prior month (0.727%). BOJ statistics show it was 0.728% from January to February 2026 and 0.727% from March onward, thus remaining stable within a very narrow band. This level is consistent with the BOJ's policy rate guidance target and indicates that short-term interest-rate control in money markets is functioning effectively.
The stable call rate despite the declining monetary base implies that acute liquidity stress has not occurred in short-term money markets. The extremely small fluctuation of 0.001% attests to the precision of BOJ operational management. In this normalization phase, quantitative tightening is advancing while interest-rate stability is maintained — a balanced policy execution.
Viewed across the past 12 months, May's monetary base of ¥575.8 trillion is the second-lowest level after March's ¥570.8 trillion. After a steady decline from ¥589.4 trillion (Jan) to ¥580.9 trillion (Feb) to ¥570.8 trillion (Mar), there was a rebound to ¥582.9 trillion in April, but May returned to a downward trajectory.
The year-on-year contraction trajectory of -9.5% (Jan) → -10.6% (Feb) → -11.6% (Mar) → -11.3% (Apr) → -12.2% (May) shows that following a temporary easing of the contraction in April, May recorded the largest year-on-year contraction in the past 12 months. This suggests the BOJ may be maintaining or even accelerating the pace of normalization.
The call rate has remained within the very tight range of 0.727%–0.728% from January through May, confirming high stability at the policy rate level. Thus, the two policy objectives — quantitative tightening and interest-rate stability — appear to be achieved concurrently.
According to the BOJ Tankan, the business conditions DI for Q1 2026 improved: large manufacturers posted 17 (previous survey 15) and large non-manufacturers 36 (previous 34). Expectations also remain cautiously positive, with large manufacturers at 15 and large non-manufacturers at 28.
The DI for medium-sized manufacturing firms was 16, unchanged from the previous survey, while small manufacturing firms improved to 7 from 6. Since Q2 2025, the large manufacturing DI has followed a steady improvement path of 13 → 14 → 15 → 17, confirming that corporate activity remains solid even as financial normalization advances.
Despite a substantial year-on-year contraction of -12.2% in the monetary base, the maintenance of improving corporate sentiment reflects the underlying resilience of the real economy and suggests that policy normalization has not produced excessive tightening effects. The call rate's stability at a low level of 0.727% also appears to have prevented a sudden deterioration in corporate financing conditions.
TOPIX rose from 3,728.73 at the start of May to 3,940.70 at month-end, recording a monthly gain of about 5.7%. Notably, on May 7 it surged by +3.00% from the previous day to 3,840.49, then underwent a mid-month adjustment before resuming an upward trend late in the month, reaching 3,957.17 on May 29.
The buoyant equity market shows that, even as monetary policy normalization proceeds, investors remain optimistic about Japan's economic outlook. It is notable that the contraction in the monetary base has not had a clear negative impact on equities. This suggests that market participants view normalization as grounded in economic health and are evaluating it positively.
TOPIX's intra-month range in May extended from 3,691.63 (May 1 low) to 3,984.58 (May 29 high), approximately 293 points, but overall the uptrend was maintained. This market resilience aligns with the improved corporate sentiment captured by the Tankan, indicating a concurrent improvement in financial conditions, the real economy, and market sentiment.
The May flash data indicate that the BOJ's policy normalization process is proceeding steadily. The year-on-year contraction pace of -12.2% in the monetary base is the largest in the past 12 months and may signal an acceleration of quantitative tightening. At the same time, the call rate remains stable at 0.727%, showing that the short-term money market is functioning well.
Key items to watch going forward are, first, the monetary base trend from June onward — whether May's contraction is temporary or the start of a new downward trend. Second is the monthly M2 money stock data due to be released within the month. M2 had risen to ¥1,295.4 trillion as of April; its May trajectory will be an important indicator for assessing private-sector demand for funds and financial intermediation.
Third, publication of additional statistics such as the Corporate Goods Price Index (CGPI) and average contracted lending rates will allow for a more detailed analysis of how normalization affects prices and lending rates. As of April, the CGPI stood at 132.8 and was trending upward; May developments will be closely watched in relation to the price-stability target.
Continued quantitative tightening while corporate sentiment and equity markets remain firm represents an ideal scenario for the BOJ. However, if the pace of monetary base contraction continues to accelerate, the impact on the financial environment must be carefully assessed. It will be necessary to wait for June and subsequent statistics releases to evaluate the sustainability of monetary policy normalization from multiple angles.
マネタリーベース: The total amount of currency supplied by the BOJ: the sum of banknote issuance, coin in circulation, and BOJ current account balances. It is a key indicator of the quantitative side of monetary policy that the central bank can directly control.
コールレート（無担保コールO/N物）: The interest rate on unsecured overnight funds traded between financial institutions. It is a representative short-term rate targeted by the BOJ's policy rate guidance.
日銀短観業況判断DI: The BOJ Tankan business conditions DI from the BOJ's quarterly short-term economic survey of firms. It equals the share of firms reporting "good" conditions minus those reporting "bad" conditions and indicates corporate sentiment.
金融政策正常化: The process of gradually transitioning from exceptional monetary easing to normal policy operations, which typically involves reducing quantitative easing measures and/or raising policy rates to adjust financial conditions to sustainable levels.
TOPIX: The Tokyo Stock Price Index. A market-capitalization-weighted index covering all issues in the Tokyo Stock Exchange Prime Market, serving as a representative indicator of the Japanese equity market.
This column was automatically generated by AI integrating Cabinet Office GDP data, Bank of Japan statistics, e-Stat public statistics, and market data as a macroeconomic analysis resource. This is not a recommendation to invest in any specific security. Please make investment decisions at your own responsibility and consult professionals as needed.