MID vs SPY
American Century Mid Cap Growth Impact ETF vs State Street SPDR S&P 500 ETF Trust
Which is better, MID or SPY?
Mid Cap Growth against Large Cap Blend.
SPY has a lower expense ratio. SPY led over 1Y and the full window. SPY is less concentrated, with 38.2% of the fund in its ten largest positions against 52.3%.
MarketXLS is not an investment adviser. This comparison is generated automatically from market data and is for information only. A Best mark means the better reading on that one measure, not a recommendation to buy.
Side-by-Side Comparison
| Metric | MID | SPY |
|---|---|---|
| Expense Ratio | 0.39% | 0.09%Best |
| AUM | $104M | $823.2B |
| Dividend Yield | 0.14% | 0.99% |
| Holdings | 35 | 1,515 |
| Volatility (annualized) | 20.3% | 15.4%Best |
| Max Drawdown | -40.1% | -24.5%Best |
| $10,000 over 6.2 years | $18,302 | $25,983Best |
| Top 10 Weight | 52.3% | 38.2%Best |
| Fund Family | American Century Investments | State Street Investment Management |
| Category | Equity | Equity |
| Style | Mid Cap Growth | Large Cap Blend |
| Inception | Jul 15, 2020 | Jan 22, 1993 |
Not shown on this pair: YTD Return, 1Y Return, 3Y Return (annualized), 5Y Return (annualized).
The two price series end 27 days apart, so a return over any period would be measuring two different stretches of market. Those rows are withheld. MID has data through Oct 9, 2026 and SPY through Nov 5, 2026.
Volatility and max drawdown, and the $10,000 over 6.2 years row, are measured over the window both funds cover: Jul 15, 2020 to Oct 9, 2026 (6.2 years).
Risk: Volatility and Drawdowns
MID has been the more volatile fund, with annualized monthly volatility of 20.3% compared with 15.4% for SPY. Lower volatility generally means a smoother ride, though it often comes with lower long-run returns.
The deepest peak-to-trough decline in our data was -40.1% for MID and -24.5% for SPY. Drawdown depth is what each fund did in the worst stretch of the window measured above.
The two funds' monthly returns correlate at 0.83. They usually move together, but the gap leaves some room for diversification.
Fees and Cost Over Time
MID charges 0.39% per year while SPY charges 0.09%. On a $10,000 position that is $39 vs $9 annually, a gap of $30 per year that compounds over a long holding period. On income, MID currently yields 0.14% against 0.99% for SPY.
Holdings Overlap
50.8% of MID's money is in holdings SPY also owns. 1.2% of SPY's money is in holdings MID also owns.
The two portfolios partly overlap.
16 positions in common, counted across the 34 positions we hold weights for in MID and 504 in SPY, against full books of 35 and 1,515.
What only one of them owns
Our book lists 481 positions for SPY that do not appear in our book for MID (98.0% of the fund), and 15 for MID that do not appear in SPY (42.5%).
Some of those will be the same company recorded under a different code in one of the two books, so the real difference in what you would own is no larger than this and may be smaller. We do not name the individual positions here for that reason.
Top Shared Holdings
| Stock | Weight in MID | Weight in SPY | Difference |
|---|---|---|---|
| MPWRMonolithic Power Systems Inc | 5.47% | 0.09% | 5.38% |
| JCIJohnson Controls Intl Plc | 4.91% | 0.13% | 4.78% |
| CDNSCadence Design Systems Inc. | 4.76% | 0.12% | 4.64% |
| TRGPTarga Resources Corp Preferred | 4.68% | 0.09% | 4.59% |
| CMGChipotle Mexican Grill Inc. Class A | 4.58% | 0.07% | 4.51% |
| HUBBHubbell Inc | 4.19% | 0.04% | 4.15% |
| HLTHilton Worldwide Holdings Inc. | 3.82% | 0.11% | 3.71% |
| VSTVistra Energy Corp. | 3.17% | 0.07% | 3.10% |
| VRTVertiv Holdings Co | 3.02% | 0.14% | 2.88% |
| RDDTReddit Inc-Cl A | 2.62% | 0.03% | 2.59% |
50.8% of MID is already inside SPY.
You probably hold more than these two. Add the rest and see how much of the whole book is the same companies twice.
Free for up to 10 holdings. No account needed.
Frequently Asked Questions
Which is cheaper, MID or SPY?
MID has an expense ratio of 0.39% while SPY charges 0.09%. SPY is the cheaper option, by $30 a year on a $10,000 investment.
Which is riskier, MID or SPY?
MID has been the more volatile fund at 20.3% annualized versus 15.4% for SPY. Worst drawdown: MID -40.1% vs SPY -24.5%.
Should I hold both MID and SPY?
MID and SPY have a monthly-return correlation of 0.83, so their returns are far enough apart for the mix to behave differently from either one alone. This is information, not a recommendation.
What is the holdings overlap between MID and SPY?
50.8% of MID's money is in holdings SPY also owns. 1.2% of SPY's is in holdings MID also owns. They hold 16 positions in common, counted across the 34 positions we hold weights for in MID and 504 in SPY.
Which pays a higher dividend, MID or SPY?
MID yields 0.14% while SPY yields 0.99%, so SPY currently pays the higher dividend yield.
Is SPY better than MID?
SPY has a lower expense ratio. SPY led over 1Y and the full window. SPY is less concentrated, with 38.2% of the fund in its ten largest positions against 52.3%. Which one suits a particular account depends on what it is for. This is information, not a recommendation.