March prices slipped into deflation, a bit of a surprise.
By David Enna, Tipswatch.com
April 30 update: I Bond gets a new fixed rate of 1.10%, composite rate of 3.98%
The just-released March inflation report gives us something we desperately need: Some clarity.
Now we know that the inflation-adjusted variable rate for the U.S. Series I Savings Bond will increase to 2.86% on May 1, up from the current 1.90%. This was finalized by the inflation report, which had non-seasonally-adjusted inflation rising 0.22% in March.
Non-seasonally-adjusted inflation increased 1.43% during the six months from October 2024 to March 2025, which translates to the new six-month annualized variable rate of 2.86%. This rate will apply to all I Bonds purchased from May to October, but will eventually roll into effect for all I Bonds no matter when they were purchased. The data:
The current variable rate, in effect for purchases through the end of April, is 1.90%. When combined with the current fixed rate of 1.2%, the I Bond’s composite rate is now 3.11% annualized. The new variable rate will increase to 2.86%, but it seems likely that the I Bond’s fixed rate will fall to 1.1% on May 1, creating a new composite rate of 3.98%.
If you buy in April, you lock in the 1.2% permanent fixed rate for up to 30 years. You will get six months of 3.11% and then six months of 4.08%. I think it makes sense to purchase in April, if you view this as a longer-term holding.
I will have more on this later this week.
The inflation report
Let the conspiracy theories begin! No, I am just kidding. However, the March inflation report, just released by the Bureau of Labor Statistics, was unusually mild.
Seasonally-adjusted all-items inflation declined 0.1% for the month and the annual rate fell from 2.8% in February to 2.4% in March. Core inflation, which removes food and energy, rose 0.1% in March and 2.8% year over year, down from 3.1% in February. All of those numbers were below consensus estimates.
Annual inflation at 2.4% is the lowest rate since last September. And it’s unusual to see a deflationary month in March. The last time that happened was March 2020, when COVID fears were sweeping the nation. So what exactly happened?
One important factor, the BLS noted, was a 6.3% decline in the price of gasoline, which is now down 9.8% year over year. On the other hand, the cost of food at home increased 0.5% for the month and 2.4% year over year.
Shelter costs increased just 0.2% for the month and are up 4.0% for the year. That was the smallest 12-month increase since November 2021. Other items from the report:
- The cost of piped gas service increased 3.6% in March after rising 2.5% in February. Those costs are now up 9.4% year over year.
- Prices for used cars and trucks fell 0.7% for the month and are up only 0.6% year over year.
- Costs of new vehicles rose just 0.1% for the month and were flat year over year. (It will be interesting to see how this changes as tariffs roll into effect.)
- Apparel costs rose 0.4% for the month and were up only 0.3% year over year. (This is another item that could be hit by rising tariffs.)
- Motor vehicle insurance costs fell 0.8% for the month but are up 7.5% year over year.
- Airline fares fell 5.3% for the month and 5.2% for the year.
Apparently, the sharp decline in gasoline prices and the moderation in shelter costs were enough to push the all-items index into deflation in March. That trend for gas and shelter could continue into much of 2025, but could be balanced off by the unknown costs of unknown future tariffs.
Here is the trend in all-items and core annual inflation over the last year:
This is exactly the type of chart President Trump and the Federal Reserve would like to see, with both core and all-items inflation falling for two consecutive months. However, the current chaos over tariffs and the brewing debt-limit crisis puts a lid on celebrations.
Do we know where inflation is heading for the rest of this year? Inflation? Deflation? It’s anyone’s guess.
What this means for TIPS
The BLS set the non-seasonally-adjusted CPI-U inflation index for March at 319.799, an increase of 0.22% from the February level. That means that principal balances for all TIPS will rise 0.22% in May, after rising 0.44% in April. Here are the new May inflation indexes for all TIPS.
What this means for future interest rates
Bloomberg is leading with the perfect headline this morning: “Trump Tariff Concerns Overshadow Upbeat US CPI Report.” This March inflation report was good news, but the positive vibes are overshadowed by tariff-related turmoil in the stock and bond markets. And, of course, tariffs seem likely to trigger higher inflation in coming months.
Bloomberg does a survey of 67 inflation forecasters and not one predicted a negative number for all-items inflation in March, and not one predicted a core increase of only 0.1%. From their economists Anna Wong and Stuart Paul:
March’s surprisingly soft CPI report showed little to no pass-through from President Trump’s initial tariff increases on Chinese imports. Apparel, furnishing, and recreation items – goods that have high import content from China – all saw either price declines or only soft price gains in March.
The real signal is that consumers are pulling back on discretionary spending. Services categories like airfares, car rentals, hotels, all saw deflation.
In all, we think the report provides space for the Fed to cut rates.
The financial markets have begun pricing in multiple rate cuts by the Federal Reserve this year, up from possibly one from earlier readings. That assumes the U.S. economy is slowing down. This March inflation report helps support the rate-cut theory, but the Fed still needs to pause and see the actual effect of tariffs on prices.
It also indicates an increasing chance of stagflation — a slowing economy combined with rising prices. From Edward Harrison, via Bloomberg:
That speaks to the Fed holding rates steady for the foreseeable future until the full economic effects of Trump’s policy changes become clearer.
• Confused by I Bonds? Read my Q&A on I Bonds
• Let’s ‘try’ to clarify how an I Bond’s interest is calculated
• Inflation and I Bonds: Track the variable rate changes
• I Bonds: Here’s a simple way to track current value
• I Bond Manifesto: How this investment can work as an emergency fund
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David Enna is a financial journalist, not a financial adviser. He is not selling or profiting from any investment discussed. I Bonds and TIPS are not “get rich” investments; they are best used for capital preservation and inflation protection. They can be purchased through the Treasury or other providers without fees, commissions or carrying charges. Please do your own research before investing.








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