PABU vs. VIIIX

Last updated Jun 4, 2026

PABU (iShares Paris-Aligned Climate Optimized MSCI USA ETF) and VIIIX (Vanguard Institutional Index Fund Institutional Plus Shares) are both funds - PABU is a Large Cap Blend Equities fund tracking the MSCI USA Climate Paris Aligned Benchmark Extended Select PAB Index (USD), while VIIIX is a S&P 500 fund tracking the S&P 500 Index. Both are passively managed. Over the past 3 years, PABU returned 20.14%/yr vs 23.17%/yr for VIIIX. Their correlation of 0.94 suggests significant overlap in exposure. PABU charges 0.10%/yr vs 0.02%/yr for VIIIX.

Performance

PABU vs. VIIIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares Paris-Aligned Climate Optimized MSCI USA ETF (PABU) and Vanguard Institutional Index Fund Institutional Plus Shares (VIIIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, PABU achieves a 9.39% return, which is significantly lower than VIIIX's 11.70% return.

PABU

• 1D: -1.29%
• 1M: 7.47%
• YTD: 9.39%
• 6M: 9.10%
• 1Y: 23.78%
• 3Y*: 20.14%
• 5Y*: —
• 10Y*: —

VIIIX

• 1D: 0.13%
• 1M: 5.80%
• YTD: 11.70%
• 6M: 11.74%
• 1Y: 28.99%
• 3Y*: 23.17%
• 5Y*: 14.42%
• 10Y*: 15.74%

*Multi-year figures are annualized to reflect compound growth (CAGR)

PABU vs. VIIIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022
PABU iShares Paris-Aligned Climate Optimized MSCI USA ETF	9.39%	13.08%	24.84%	29.51%	-15.45%
VIIIX Vanguard Institutional Index Fund Institutional Plus Shares	11.70%	17.87%	26.29%	25.79%	-11.83%

Correlation

The correlation between PABU and VIIIX is 0.95 - these two move nearly in lockstep. At this level, holding both provides almost no diversification benefit. If you already own one, adding the other does little to reduce portfolio risk.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.95
Correlation (3Y) Calculated over the trailing 3-year period	0.97
Correlation (All Time) Calculated using the full available price history since Feb 14, 2022	0.94

The correlation between PABU and VIIIX has been stable across timeframes, ranging from 0.94 to 0.97 - a consistent structural relationship.

PABU vs. VIIIX - Sectors Allocation Comparison

Sectors	PABU	VIIIX
Technology	44.9%	35.5%
Real Estate	12.4%	1.9%
Financial Services	11.2%	11.6%
Communication Services	10.4%	11.1%
Consumer Cyclical	9.0%	10.0%
Healthcare	7.4%	8.5%
Industrials	2.5%	8.0%
Utilities	1.8%	2.8%
Energy	0.7%	3.5%
Basic Materials	0.5%	1.8%
Consumer Defensive	-	4.9%

Return for Risk

PABU vs. VIIIX — Risk / Return Rank

Compare risk-adjusted metric ranks to identify better-performing investments over the past 12 months.

PABU

PABU Risk / Return Rank: 46
PABU Sharpe Ratio Rank: 52
PABU Sortino Ratio Rank: 51
PABU Omega Ratio Rank: 50
PABU Calmar Ratio Rank: 36
PABU Martin Ratio Rank: 40

VIIIX

VIIIX Risk / Return Rank: 73
VIIIX Sharpe Ratio Rank: 76
VIIIX Sortino Ratio Rank: 67
VIIIX Omega Ratio Rank: 67
VIIIX Calmar Ratio Rank: 74
VIIIX Martin Ratio Rank: 83

The rank (0–100) shows how this investment's returns compare to the risk taken. Higher = better. Based on the past 12 months of data, combining Sharpe, Sortino, and other metrics used by quantitative funds and institutional investors.

PABU vs. VIIIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares Paris-Aligned Climate Optimized MSCI USA ETF (PABU) and Vanguard Institutional Index Fund Institutional Plus Shares (VIIIX). Risk-adjusted metrics are performance indicators that assess an investment's returns in relation to its risk, enabling a more accurate comparison of different investment options.

	PABU	VIIIX	Difference
Sharpe ratio: Return per unit of total volatility	1.79	2.52	-0.73
Sortino ratio: Return per unit of downside risk	2.48	3.42	-0.95
Omega ratio: Gain probability vs. loss probability	1.31	1.46	-0.14
Calmar ratio: Return relative to maximum drawdown	1.78	3.36	-1.58
Martin ratio: Return relative to average drawdown	6.25	15.69	-9.45
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

PABU vs. VIIIX - Sharpe Ratio Comparison

The current PABU Sharpe Ratio is 1.79, which is comparable to the VIIIX Sharpe Ratio of 2.52. The chart below compares the historical Sharpe Ratios of PABU and VIIIX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Sharpe Ratios by Period

	PABU	VIIIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.79	2.52	-0.73
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	—	0.86	—
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	—	0.87	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.73	0.50	+0.23

Drawdowns

PABU vs. VIIIX - Drawdown Comparison

The maximum PABU drawdown since its inception was -22.76%, smaller than the maximum VIIIX drawdown of -55.18%. Use the drawdown chart below to compare losses from any high point for PABU and VIIIX.

Drawdown Indicators

	PABU	VIIIX	Difference
Max Drawdown Largest peak-to-trough decline	-22.76%	-55.18%	+32.42%
Max Drawdown (1Y) Largest decline over 1 year	-13.40%	-8.90%	-4.50%
Max Drawdown (3Y) Largest decline over 3 years	-20.85%	-18.75%	-2.10%
Max Drawdown (5Y) Largest decline over 5 years	—	-24.50%	—
Max Drawdown (10Y) Largest decline over 10 years	—	-33.79%	—
Current Drawdown Current decline from peak	-1.29%	0.00%	-1.29%
Average Drawdown Average peak-to-trough decline	-5.63%	-10.02%	+4.39%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.82%	1.90%	+1.92%

Volatility

PABU vs. VIIIX - Volatility Comparison

iShares Paris-Aligned Climate Optimized MSCI USA ETF (PABU) has a higher volatility of 3.70% compared to Vanguard Institutional Index Fund Institutional Plus Shares (VIIIX) at 2.83%. This indicates that PABU's price experiences larger fluctuations and is considered to be riskier than VIIIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	PABU	VIIIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.70%	2.83%	+0.87%
Volatility (6M) Calculated over the trailing 6-month period	10.24%	8.97%	+1.27%
Volatility (1Y) Calculated over the trailing 1-year period	13.37%	11.86%	+1.51%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	18.68%	16.89%	+1.79%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.68%	18.06%	+0.62%

PABU vs. VIIIX - Expense Ratio Comparison

PABU has a 0.10% expense ratio, which is higher than VIIIX's 0.02% expense ratio. However, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

PABU vs. VIIIX - Dividend Comparison

PABU's dividend yield for the trailing twelve months is around 0.86%, less than VIIIX's 2.41% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
PABU iShares Paris-Aligned Climate Optimized MSCI USA ETF	0.86%	0.90%	1.00%	1.06%	1.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
VIIIX Vanguard Institutional Index Fund Institutional Plus Shares	2.41%	2.11%	3.66%	2.66%	3.39%	4.79%	3.07%	2.86%	2.45%	1.84%	2.38%	2.47%

Frequently Asked Questions

Can I hold both PABU and VIIIX in my portfolio?

With a correlation of 0.95, PABU and VIIIX move almost identically. Holding both adds very little diversification - you're essentially doubling your position in the same market segment. Choosing one is usually more capital-efficient.

Which is riskier, PABU or VIIIX?

PABU has higher volatility (3.70%) compared to VIIIX (2.83%). In terms of maximum drawdown, PABU dropped -22.76% vs VIIIX's -55.18%.

Which has better risk-adjusted returns?

VIIIX currently has the higher Sharpe Ratio (2.52 vs 1.79), meaning it's delivered slightly more return per unit of risk over the trailing 12 months. However, this ranking shifts over time - use the Risk/Return Score above for a more comprehensive view that combines Sharpe, Sortino, and other measures used by quantitative funds.