CSTL vs. USAR

Last updated Jun 4, 2026

CSTL (Castle Biosciences, Inc.) and USAR (USA Rare Earth, Inc) are both stocks. CSTL operates in Diagnostics & Research (Healthcare), while USAR operates in Other Industrial Metals & Mining (Basic Materials). Over the past year, CSTL returned 22.02% vs 208.15% for USAR. At a 0.09 correlation, their price movements are largely independent.

Performance

CSTL vs. USAR - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Castle Biosciences, Inc. (CSTL) and USA Rare Earth, Inc (USAR). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, CSTL achieves a -47.58% return, which is significantly lower than USAR's 135.13% return.

CSTL

• 1D: 3.45%
• 1M: -20.10%
• YTD: -47.58%
• 6M: -48.26%
• 1Y: 22.02%
• 3Y*: -3.56%
• 5Y*: -20.27%
• 10Y*: —

USAR

• 1D: -8.86%
• 1M: 9.38%
• YTD: 135.13%
• 6M: 99.57%
• 1Y: 208.15%
• 3Y*: —
• 5Y*: —
• 10Y*: —

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

CSTL vs. USAR - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023
CSTL Castle Biosciences, Inc.	-47.58%	45.97%	23.49%	30.79%
USAR USA Rare Earth, Inc	135.13%	3.66%	11.13%	2.58%

Correlation

The correlation between CSTL and USAR is 0.15, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.15
Correlation (All Time) Calculated using the full available price history since Jul 18, 2023	0.09

Fundamentals

EPS CSTL : -$0.44 USAR : -$4.85
PS Ratio CSTL : 1.77 USAR : 7.51
Total Revenue (TTM) CSTL : $339.92M USAR : $319.83M
Gross Profit (TTM) CSTL : $164.74M USAR : $253.66M
EBITDA (TTM) CSTL : $9.62M USAR : -$324.99M

Return for Risk

CSTL vs. USAR — Risk / Return Rank

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

CSTL

CSTL Risk / Return Rank: 53
CSTL Sharpe Ratio Rank: 54
CSTL Sortino Ratio Rank: 54
CSTL Omega Ratio Rank: 55
CSTL Calmar Ratio Rank: 50
CSTL Martin Ratio Rank: 51

USAR

USAR Risk / Return Rank: 80
USAR Sharpe Ratio Rank: 84
USAR Sortino Ratio Rank: 83
USAR Omega Ratio Rank: 77
USAR Calmar Ratio Rank: 82
USAR 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.

CSTL vs. USAR - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Castle Biosciences, Inc. (CSTL) and USA Rare Earth, Inc (USAR). 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.

	CSTL	USAR	Difference
Sharpe ratio: Return per unit of total volatility	0.35	1.71	-1.36
Sortino ratio: Return per unit of downside risk	0.99	2.62	-1.63
Omega ratio: Gain probability vs. loss probability	1.14	1.28	-0.15
Calmar ratio: Return relative to maximum drawdown	0.38	3.03	-2.64
Martin ratio: Return relative to average drawdown	0.88	5.02	-4.14
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

CSTL vs. USAR - Sharpe Ratio Comparison

The current CSTL Sharpe Ratio is 0.35, which is lower than the USAR Sharpe Ratio of 1.71. The chart below compares the historical Sharpe Ratios of CSTL and USAR, 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

	CSTL	USAR	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.35	1.71	-1.36
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.27	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	-0.01	0.41	-0.42

Drawdowns

CSTL vs. USAR - Drawdown Comparison

The maximum CSTL drawdown since its inception was -88.02%, which is greater than USAR's maximum drawdown of -69.23%. Use the drawdown chart below to compare losses from any high point for CSTL and USAR.

Drawdown Indicators

	CSTL	USAR	Difference
Max Drawdown Largest peak-to-trough decline	-88.02%	-69.23%	-18.79%
Max Drawdown (1Y) Largest decline over 1 year	-57.83%	-69.23%	+11.40%
Max Drawdown (3Y) Largest decline over 3 years	-57.83%	—	—
Max Drawdown (5Y) Largest decline over 5 years	-84.97%	—	—
Current Drawdown Current decline from peak	-79.05%	-27.66%	-51.39%
Average Drawdown Average peak-to-trough decline	-54.66%	-18.60%	-36.06%
Ulcer Index Depth and duration of drawdowns from previous peaks	24.98%	41.62%	-16.64%

Volatility

CSTL vs. USAR - Volatility Comparison

Castle Biosciences, Inc. (CSTL) and USA Rare Earth, Inc (USAR) have volatilities of 30.06% and 30.06%, respectively, indicating that both stocks experience similar levels of price fluctuations. This suggests that the risk associated with both stocks, as measured by volatility, is nearly the same. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	CSTL	USAR	Difference
Volatility (1M) Calculated over the trailing 1-month period	30.06%	30.06%	0.00%
Volatility (6M) Calculated over the trailing 6-month period	41.23%	81.05%	-39.82%
Volatility (1Y) Calculated over the trailing 1-year period	63.45%	122.97%	-59.52%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	74.24%	104.42%	-30.18%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	74.36%	104.42%	-30.06%

Dividends

CSTL vs. USAR - Dividend Comparison

Neither CSTL nor USAR has paid dividends to shareholders.

Tickers have no history of dividend payments

Financials

Frequently Asked Questions

Can I hold both CSTL and USAR in my portfolio?

CSTL and USAR have a correlation of 0.15, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, CSTL or USAR?

USAR has higher volatility (30.06%) compared to CSTL (30.06%). In terms of maximum drawdown, CSTL dropped -88.02% vs USAR's -69.23%.

Which has better risk-adjusted returns?

USAR currently has the higher Sharpe Ratio (1.71 vs 0.35), 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.