IWO
iShares Russell 2000 Growth ETF
SMB
RMW
Adj. R2
0.979
Rel. Sharpe
0.591
Mkt beta
1.13
AUM
US$12.9B
MER
0.24%
Valuation
140
ETF comparison
Verified factor-similar pair
IWO vs VTWG
These US-listed equity ETFs share verified FF6 US factor exposure. The modeled volatility of their factor-return difference is at or below 3% annualized on both the same 36-month window and a longer factor-history check.
SMB
Current similarity score
99
Very close factor fit
The score is 100 for identical fitted exposures and 80 at the 3% modeled tracking-error limit. It includes market and non-market factors; it does not indicate which fund earned or is expected to earn more. How to read this score.
Quick Read
- VTWG has the higher backtested relative Sharpe (0.660 vs 0.591).
- VTWG has the lower published fee (0.06% vs 0.24%).
- VTWG is cheaper on dividend valuation (95 vs 140, where 100 is each fund's historical median).
These are screening signals, not a complete review of portfolio construction, turnover, taxes, or trading quality.
VTWG
Vanguard Russell 2000 Growth ETF
SMB
UMD
Adj. R2
0.983
Rel. Sharpe
0.660
Mkt beta
1.14
AUM
US$1.3B
MER
0.06%
Valuation
95
Market beta uses the common 36-month window through 2026-08. Adjusted R² and relative Sharpe describe each fund's separately published full-history model.
Factor Exposure Match
Blue bars compare factor beta magnitude from the same 36 months shown above. Green bars compare absolute t-stat strength; dim bars indicate |t| below 1.96. Every factor enters the distance calculation regardless of its t-statistic.
SMB
diff -0.01
HML
diff +0.00
RMW
diff -0.01
CMA
diff -0.01
UMD
diff -0.00
What Happened Over the Same 36 Months
IWO adjusted total-return CAGR
16.91%
VTWG adjusted total-return CAGR
17.07%
VTWG ahead by 0.17 percentage points/year over 2023-09 through 2026-08. This is the observed difference between annualized compounded returns from adjusted prices, not an expected return or a factor-model estimate.
Historical factor attribution
Signed contribution to IWO minus VTWG, percentage points/year, using fitted 36-month exposures and average factor returns over those same months:
Market factor
-0.14
Other factors, combined
+0.11
Total factor-implied difference
-0.02
This arithmetic-average factor attribution excludes the regression intercept and fund-specific return. It therefore need not equal the observed CAGR difference and is not a forecast.
Why This Pair Matches
Modeled factor tracking error · 36m
0.16%/yr
Modeled tracking error · 120m factor history
0.18%/yr
Mkt beta diff
0.01
Rel. Sharpe diff
0.069
Fitted exposures and factor covariance estimate the volatility, not the average or direction, of the funds' modeled return difference. The common regression window is 2023-09 through 2026-08. A short-window estimate and a longer factor-history check must both be at or below 3.000%; this is a screening limit, not a forecast. Holdings, turnover, taxes and trading costs require a separate review. The Sharpe figures elsewhere on this page come from each fund's published full-history model and do not enter similarity ranking. See the full methodology.
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