10-Year TIPS Real Yield Reaches 2.78% as S&P 500 Gains 16.8%

The 10-year Treasury Inflation-Protected Securities (TIPS) yield ended Oct. 15 at 2.78%, compared with 1.71% a year earlier. Over the same period, the S&P 500 advanced 16.8%. The index’s forward price-to-earnings ratio declined from 22.4 to 19.0 as forward earnings estimates increased about 38%.

Earnings drove the gain. With the earnings yield about 2.5 points above the TIPS yield, each quarter-point increase in real yields equates to roughly 4.5% of index value if estimates remain unchanged. On Sept. 17, the morning after the Federal Reserve raised its benchmark rate for the first time since 2023, the Treasury auctioned $19 billion in 10-year TIPS at a real yield of 2.653%.

That was the highest auction yield for that maturity since October 2008. In theory, higher real yields should make stocks less attractive to own. Yet the S&P 500 closed at 7,744.06 on Oct. 15, a 16.8% increase from a year earlier, according to FRED index data.

The 10-year real yield rose from 1.71% to 2.78%, near its highest level since the 2008 financial crisis. The arithmetic suggests stock investors did not ignore the bond market. The Multiple Shrank 15% And The Index Still Rose 17% An index price is the product of two figures: expected earnings per share and the multiple. Separating the price and valuation figures shows a textbook repricing in which earnings growth outpaced multiple compression.

FactSet’s Oct. 17, 2025 report put the S&P 500’s forward 12-month P/E at 22.4. Its latest Earnings Insight, dated Oct. 16, 2026, puts the multiple at 19.0, below the five-year average of 19.8.

Dividing the index price by its multiple implies forward earnings of about $296 a share a year ago and $408 now. A 15% smaller multiple applied to 38% more earnings yields almost exactly the 17% price gain. Rates weighed on the market, but earnings growth had a larger effect. Chris Carpentier, a senior investment strategist at State Street Investment Management, reached a similar conclusion in a Sept.

21 note. “Markets are still responding to higher discount rates in a manner broadly consistent with financial theory,” he wrote. Two Measures Of The Cushion Point Different Ways The equity risk premium (ERP) is the additional annual return investors demand for holding stocks rather than a risk-free bond. When the premium is thin, even a modest rate shock can erase months of gains.

It cannot be observed directly. A basic estimate subtracts the real yield from the forward earnings yield, the inverse of the P/E. At 19.0 times earnings, that yield is 5.26%, or The premium over the TIPS yield is 2.48 percentage points, versus 2.75 points a year earlier, when real yields were more than a full point lower. That cushion has narrowed by 0.27.

Aswath Damodaran, a finance professor at NYU Stern, reaches a different conclusion using his cash-flow model. His implied ERP series increased to 4.20% on Oct. 1 from 3.78% a year earlier, while the Treasury rate in his model rose to 5.29% from 4.16%. His trailing cash-yield measure eased to 3.70% from 4.01%, aligning more closely with Carpentier’s view that the premium “has compressed and remains at lows.” Forward-earnings measures rely on analysts’ forecasts, while cash-yield measures assume the previous year will repeat.

Neither indicates that stocks are cheap relative to TIPS. The conclusion depends on the method used. Two Chipmakers Account for 9 Points of Earnings Growth The earnings increase is concentrated. FactSet’s blended third-quarter growth rate is 29.0%; excluding Micron Technology Inc.

(NASDAQ: MU) and NVIDIA Corp. (NASDAQ: NVDA), it drops to 20.0%. Growth is expected to slow. FactSet consensus projects 16.0% for calendar 2027, but just 2.8% for the second quarter of 2027 as year-ago comparisons become more demanding.

Sector multiples range from 13.3 times forward earnings for Energy’s sensitivity rises to 23.4 for Consumer Discretionary. The relationship is steep: with the 2.48-point cushion unchanged and earnings estimates flat, a quarter-point increase in the real yield implies a P/E near 18.1 and prices about 4.5% lower. A half-point increase points to roughly 17.4 times earnings and an 8.7% decline, while a half-point decrease supports about 21 times earnings. A quarter-point hike would not reopen the Strait of Hormuz.

At the Sept. 16 press conference, CBS reporter Richard Escobedo made that point to Chair Kevin Warsh. Warsh responded that the Fed “cannot affect any individual price,” but can prevent relative price changes from broadening, according to the official transcript. The September CPI report showed headline inflation at 3.7%, including a 34.2% rise in gasoline over 12 months; core inflation was 2.6%.

EIA weekly data show regular gasoline averaged $4.33 a gallon in the week of Oct. 12, compared with $3.06 a year earlier. The CPI release briefly lifted rate-hike bets, according to a report. The bond market is treating the shock as temporary.

The 10-year breakeven rate—the inflation rate at which TIPS and ordinary Treasuries of the same maturity return The same measure was 2.35% on Oct. 16, alongside the Fed’s median forecast of 2.3% inflation in 2027, based on its preferred PCE gauge. Warsh described one Fed objective as keeping “inflation compensation in market prices” low. That sets a hurdle for investors: TIPS outperform nominal 10-year Treasuries only if inflation averages more than about 2.35% over the decade.

Warsh also noted that inflation has exceeded the target for more than five years. Inflation protection does not prevent price losses. The iShares TIPS Bond ETF (NYSE: TIP) has a 2.81% real yield and 6.19-year effective duration, but its net asset value total return was negative 0.95% year to date as of Oct. 15.

Real yields have risen 0.84 points this year; the duration implies an approximate 6% price decline for each full-point increase. What the 2.8% hurdle means for a portfolio A risk-free real return near 2.8% now sets the benchmark for risk assets, while stocks clear it by a narrower margin than a year ago. One way to compare stocks with the real yield is to use the forward earnings yield minus the 10-year TIPS yield. That spread, now 2.48 points, can serve as a cushion gauge; FactSet’s weekly revisions indicate its direction.

Match the instrument to the date. Individual TIPS held until maturity lock in their real yield, while a fund such as TIP has no maturity date and its price can move with real yields. Under TreasuryDirect rules, annual changes in principal may affect federal taxes, making account location relevant. Investors should also check for allocation drift.

A stock-and-TIPS mix established a year ago, for example using the State Street SPDR S&P 500 ETF Trust (NYSE: SPY) and TIP, has likely shifted toward stocks. Written rebalancing bands determine when that drift prompts a trade. Upcoming catalysts include the first “Magnificent 7” reports, listed by FactSet for Oct. 21, and the Federal Open Market Committee meeting on Oct.

27-28. Traders in prediction markets put the odds of an October hike at 14%. Equities have absorbed higher real yields as earnings grew faster than the discount rate rose; if that relationship reverses, earnings would show it first. Stocks now face a specific benchmark.

At the Oct. 15 real yield, $100,000 invested in a 10-year TIPS and held to maturity would grow to about $131,500 in today’s purchasing power, before taxes.