ALRT.L vs. VOO

Last updated Apr 1, 2026

Compare and contrast key facts about Defence Holdings PLC (ALRT.L) and Vanguard S&P 500 ETF (VOO).

VOO is a passively managed fund by Vanguard that tracks the performance of the S&P 500 Index. It was launched on Sep 7, 2010.

Performance

ALRT.L vs. VOO - Performance Comparison

The chart below illustrates the hypothetical performance of a £10,000 investment in Defence Holdings PLC (ALRT.L) and Vanguard S&P 500 ETF (VOO). The values are adjusted to include any dividend payments, if applicable.

ALRT.L vs. VOO - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020
ALRT.L Defence Holdings PLC	-25.71%	4,566.67%	-95.31%	-38.46%	-59.38%	-42.86%	-31.29%
VOO Vanguard S&P 500 ETF	-2.60%	9.43%	27.16%	20.01%	-8.44%	30.01%	6.54%

Different Trading Currencies

ALRT.L is traded in GBp, while VOO is traded in USD. To make them comparable, the VOO values have been converted to GBp using the latest available exchange rates.

Returns By Period

In the year-to-date period, ALRT.L achieves a -25.71% return, which is significantly lower than VOO's -5.22% return.

ALRT.L

• 1D: 7.44%
• 1M: -4.41%
• YTD: -25.71%
• 6M: -67.90%
• 1Y: 2,376.19%
• 3Y*: 10.06%
• 5Y*: -25.46%
• 10Y*: —

VOO

• 1D: 0.00%
• 1M: -5.75%
• YTD: -5.22%
• 6M: -2.84%
• 1Y: 11.87%
• 3Y*: 14.51%
• 5Y*: 12.15%
• 10Y*: 14.57%

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

Return for Risk

ALRT.L vs. VOO — Risk / Return Rank

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

ALRT.L

ALRT.L Risk / Return Rank: 99
ALRT.L Sharpe Ratio Rank: 100
ALRT.L Sortino Ratio Rank: 99
ALRT.L Omega Ratio Rank: 98
ALRT.L Calmar Ratio Rank: 100
ALRT.L Martin Ratio Rank: 100

VOO

VOO Risk / Return Rank: 65
VOO Sharpe Ratio Rank: 59
VOO Sortino Ratio Rank: 62
VOO Omega Ratio Rank: 66
VOO Calmar Ratio Rank: 65
VOO Martin Ratio Rank: 75

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.

ALRT.L vs. VOO - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Defence Holdings PLC (ALRT.L) and Vanguard S&P 500 ETF (VOO). 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.

	ALRT.L	VOO	Difference
Sharpe ratio Return per unit of total volatility	10.08	0.65	+9.43
Sortino ratio Return per unit of downside risk	6.24	1.02	+5.22
Omega ratio Gain probability vs. loss probability	1.70	1.16	+0.54
Calmar ratio Return relative to maximum drawdown	35.10	1.09	+34.01
Martin ratio Return relative to average drawdown	56.67	4.41	+52.25
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

ALRT.L vs. VOO - Sharpe Ratio Comparison

The current ALRT.L Sharpe Ratio is 10.08, which is higher than the VOO Sharpe Ratio of 0.65. The chart below compares the historical Sharpe Ratios of ALRT.L and VOO, offering insights into how both investments have performed under varying market conditions. These values are calculated using daily returns over the previous 12 months.

Sharpe Ratios by Period

	ALRT.L	VOO	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	10.08	0.65	+9.43
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.17	0.77	-0.94
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	—	0.81	—
Sharpe Ratio (All Time) Calculated using the full available price history	-0.20	0.88	-1.08

Correlation

The correlation between ALRT.L and VOO is -0.01. This indicates that the assets' prices tend to move in opposite directions. Negative correlation can be particularly beneficial for diversification and risk management, as one asset may offset the losses of the other during market fluctuations.

Dividends

ALRT.L vs. VOO - Dividend Comparison

ALRT.L has not paid dividends to shareholders, while VOO's dividend yield for the trailing twelve months is around 1.19%.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
ALRT.L Defence Holdings PLC	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
VOO Vanguard S&P 500 ETF	1.19%	1.13%	1.24%	1.46%	1.69%	1.25%	1.54%	1.88%	2.06%	1.78%	2.02%	2.10%

Drawdowns

ALRT.L vs. VOO - Drawdown Comparison

The maximum ALRT.L drawdown since its inception was -99.62%, which is greater than VOO's maximum drawdown of -26.09%. Use the drawdown chart below to compare losses from any high point for ALRT.L and VOO.

Drawdown Indicators

	ALRT.L	VOO	Difference
Max Drawdown Largest peak-to-trough decline	-99.62%	-33.99%	-65.63%
Max Drawdown (1Y) Largest decline over 1 year	-75.12%	-11.98%	-63.14%
Max Drawdown (5Y) Largest decline over 5 years	-99.62%	-24.52%	-75.10%
Max Drawdown (10Y) Largest decline over 10 years	—	-33.99%	—
Current Drawdown Current decline from peak	-84.24%	-6.29%	-77.95%
Average Drawdown Average peak-to-trough decline	-74.57%	-3.72%	-70.85%
Ulcer Index Depth and duration of drawdowns from previous peaks	46.53%	2.52%	+44.01%

Volatility

ALRT.L vs. VOO - Volatility Comparison

Defence Holdings PLC (ALRT.L) has a higher volatility of 25.24% compared to Vanguard S&P 500 ETF (VOO) at 3.52%. This indicates that ALRT.L's price experiences larger fluctuations and is considered to be riskier than VOO based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	ALRT.L	VOO	Difference
Volatility (1M) Calculated over the trailing 1-month period	25.24%	3.52%	+21.72%
Volatility (6M) Calculated over the trailing 6-month period	86.07%	9.07%	+77.00%
Volatility (1Y) Calculated over the trailing 1-year period	232.63%	18.36%	+214.27%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	149.72%	15.77%	+133.95%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	144.11%	18.10%	+126.01%