The Federal Reserve is widely expected to raise interest rates again at next month’s FOMC meeting. Using the futures market for Fed funds as a guide, another round of tightening is a virtual certainty. The ongoing rebound in the inflation-adjusted monetary base, however, suggests that there’s still room for debate.

The Fed’s narrowest gauge of money supply – aka M0 – increased 5.1% in real terms for the year through October, based on monthly data. That’s the strongest annual gain in three years and the longest run of increases since early 2015.

The revival in real M0’s annual pace raises questions about the Fed’s near-term commitment to squeezing monetary policy. After two years of negative year-over-year readings for the inflation-adjusted base money’s trend, the recent U-turn into positive terrain hints at a slower pace of policy tapering than previously assumed. All the more so given the acceleration in M0’s revival.

Interpreting the Fed’s intentions via a narrow measure of money supply is far from foolproof, although the track record for this data isn’t easily dismissed. History reminds that M0’s inflation-adjusted annual trend has been a relatively reliable proxy for measuring the Fed’s monetary policy stance in real time. For example, real M0 offered a clue in early 2015 that the Fed was close to tightening policy for the first time in nearly a decade. Later that year, in December 2015, the central bank announced that it was raising the target range for the federal funds rate. The central bank has increased rates several times since then.

Will the hawkish bias will roll on at next month’s FOMC meeting that’s scheduled for Dec. 12-13? Yes, it’s a virtual certainty, according to Fed funds futures. The probability of a rate hike next month is 97%, according to CME data this morning.

Recent economic data offers no reason to think otherwise. Notably, GDP growth has been solid at 3%-plus in the second and third quarters and the latest estimates for Q4 point to another 3% rise. The Atlanta Fed’s GDPNow model is looking for a 3.2% rise in the final three months of this year while Now-casting.com’s current analysis calls for an increase of nearly 3.9%.

Meanwhile, yesterday’s retail sales report shows that the year-over-year trend in consumer spending is holding steady at a relatively upbeat 4.6%. Inflation is still below the Fed’s 2.0% target, although the core reading for the consumer price index ticked up to a 1.8% year-over-year rise — the first acceleration since January.

What, then, is prompting the Fed’s volte-face with M0? Perhaps the monetary overlords are having second thoughts about raising rates in the immediate future after looking at the ongoing slowdown in business-lending growth. Commercial and industrial loans issued by commercial banks rose just 1.3% for the year through October – the softest increase in over six years.

Nonetheless, hawkish expectations prevail and most analysts think that the Fed remains on track to raise its target rate once more next month. That’s still a reasonable bet, although the resurgence in M0 growth implies that a December surprise can’t be ruled out.