CAIBX vs. TIBAX

Last updated Jun 4, 2026

CAIBX (American Funds Capital Income Builder Class A) and TIBAX (Thornburg Investment Income Builder Fund) are both mutual funds - CAIBX is a Diversified Portfolio fund managed by American Funds, while TIBAX is a Global Allocation fund managed by Thornburg. Over the past 10 years, CAIBX returned 7.94%/yr vs 12.42%/yr for TIBAX. Their correlation of 0.87 suggests significant overlap in exposure. CAIBX charges 0.59%/yr vs 1.14%/yr for TIBAX.

Performance

CAIBX vs. TIBAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Funds Capital Income Builder Class A (CAIBX) and Thornburg Investment Income Builder Fund (TIBAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, CAIBX achieves a 7.79% return, which is significantly lower than TIBAX's 17.92% return. Over the past 10 years, CAIBX has underperformed TIBAX with an annualized return of 7.94%, while TIBAX has yielded a comparatively higher 12.42% annualized return.

CAIBX

• 1D: 0.57%
• 1M: 2.03%
• YTD: 7.79%
• 6M: 8.56%
• 1Y: 18.52%
• 3Y*: 15.22%
• 5Y*: 8.54%
• 10Y*: 7.94%

TIBAX

• 1D: 0.63%
• 1M: 3.10%
• YTD: 17.92%
• 6M: 21.20%
• 1Y: 39.47%
• 3Y*: 26.52%
• 5Y*: 16.15%
• 10Y*: 12.42%

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

CAIBX vs. TIBAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
CAIBX American Funds Capital Income Builder Class A	7.79%	20.39%	10.24%	8.95%	-7.14%	14.99%	3.20%	17.23%	-7.28%	13.99%
TIBAX Thornburg Investment Income Builder Fund	17.92%	36.62%	13.23%	18.01%	-7.95%	20.08%	-0.67%	17.72%	-4.54%	14.83%

Correlation

The correlation between CAIBX and TIBAX is 0.75, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.75
Correlation (3Y) Calculated over the trailing 3-year period	0.82
Correlation (5Y) Calculated over the trailing 5-year period	0.85
Correlation (10Y) Calculated over the trailing 10-year period	0.86
Correlation (All Time) Calculated using the full available price history since Dec 26, 2002	0.87

The correlation between CAIBX and TIBAX shifts across timeframes, from 0.75 (1 year) to 0.87 (all time), reflecting how their relationship changes across market environments.

Return for Risk

CAIBX vs. TIBAX — Risk / Return Rank

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

CAIBX

CAIBX Risk / Return Rank: 60
CAIBX Sharpe Ratio Rank: 64
CAIBX Sortino Ratio Rank: 62
CAIBX Omega Ratio Rank: 62
CAIBX Calmar Ratio Rank: 57
CAIBX Martin Ratio Rank: 57

TIBAX

TIBAX Risk / Return Rank: 98
TIBAX Sharpe Ratio Rank: 99
TIBAX Sortino Ratio Rank: 98
TIBAX Omega Ratio Rank: 97
TIBAX Calmar Ratio Rank: 97
TIBAX Martin Ratio Rank: 98

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.

CAIBX vs. TIBAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Funds Capital Income Builder Class A (CAIBX) and Thornburg Investment Income Builder Fund (TIBAX). 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.

	CAIBX	TIBAX	Difference
Sharpe ratio: Return per unit of total volatility	2.34	4.75	-2.41
Sortino ratio: Return per unit of downside risk	3.31	6.82	-3.51
Omega ratio: Gain probability vs. loss probability	1.44	1.96	-0.52
Calmar ratio: Return relative to maximum drawdown	2.89	7.36	-4.47
Martin ratio: Return relative to average drawdown	11.49	28.70	-17.21
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

CAIBX vs. TIBAX - Sharpe Ratio Comparison

The current CAIBX Sharpe Ratio is 2.34, which is lower than the TIBAX Sharpe Ratio of 4.75. The chart below compares the historical Sharpe Ratios of CAIBX and TIBAX, 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

	CAIBX	TIBAX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.34	4.75	-2.41
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.86	1.46	-0.60
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.73	0.93	-0.19
Sharpe Ratio (All Time) Calculated using the full available price history	0.92	0.80	+0.13

Drawdowns

CAIBX vs. TIBAX - Drawdown Comparison

The maximum CAIBX drawdown since its inception was -43.68%, smaller than the maximum TIBAX drawdown of -49.12%. Use the drawdown chart below to compare losses from any high point for CAIBX and TIBAX.

Drawdown Indicators

	CAIBX	TIBAX	Difference
Max Drawdown Largest peak-to-trough decline	-43.68%	-49.12%	+5.44%
Max Drawdown (1Y) Largest decline over 1 year	-6.47%	-5.43%	-1.04%
Max Drawdown (3Y) Largest decline over 3 years	-8.89%	-9.20%	+0.31%
Max Drawdown (5Y) Largest decline over 5 years	-17.65%	-20.94%	+3.29%
Max Drawdown (10Y) Largest decline over 10 years	-25.28%	-34.85%	+9.57%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-3.81%	-5.99%	+2.18%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.63%	1.39%	+0.24%

Volatility

CAIBX vs. TIBAX - Volatility Comparison

The current volatility for American Funds Capital Income Builder Class A (CAIBX) is 2.47%, while Thornburg Investment Income Builder Fund (TIBAX) has a volatility of 3.12%. This indicates that CAIBX experiences smaller price fluctuations and is considered to be less risky than TIBAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	CAIBX	TIBAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.47%	3.12%	-0.65%
Volatility (6M) Calculated over the trailing 6-month period	6.42%	6.97%	-0.55%
Volatility (1Y) Calculated over the trailing 1-year period	8.00%	8.42%	-0.42%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	9.98%	11.12%	-1.14%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	10.88%	13.46%	-2.58%

CAIBX vs. TIBAX - Expense Ratio Comparison

CAIBX has a 0.59% expense ratio, which is lower than TIBAX's 1.14% expense ratio.

Dividends

CAIBX vs. TIBAX - Dividend Comparison

CAIBX's dividend yield for the trailing twelve months is around 7.22%, more than TIBAX's 4.85% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
CAIBX American Funds Capital Income Builder Class A	7.22%	7.71%	5.76%	3.47%	3.43%	3.14%	3.38%	4.10%	3.55%	4.44%	3.52%	3.62%
TIBAX Thornburg Investment Income Builder Fund	4.85%	5.64%	5.44%	4.67%	5.62%	5.10%	4.11%	4.23%	4.49%	4.22%	3.83%	4.31%

Frequently Asked Questions

Can I hold both CAIBX and TIBAX in my portfolio?

CAIBX and TIBAX have a correlation of 0.75, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, CAIBX or TIBAX?

TIBAX has higher volatility (3.12%) compared to CAIBX (2.47%). In terms of maximum drawdown, CAIBX dropped -43.68% vs TIBAX's -49.12%.

Which has better risk-adjusted returns?

TIBAX currently has the higher Sharpe Ratio (4.75 vs 2.34), 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.