This bond ETF tracks the Markit iBoxx USD Liquid Investment Grade Index and diversifies across US investment grade corporate bonds. It holds highly liquid, high-quality corporate bonds with a minimum remaining time to maturity, weighted by market value.

It suits core bond investors who want stable interest income with lower volatility than stocks, along with diversification benefits.

It is a passive (index-tracking) ETF managed by BlackRock (iShares).

The fund tracks the index using a representative sampling approach, holding US dollar denominated corporate bonds classified as investment grade that meet outstanding issuance size and liquidity criteria. Bonds are included by market value weight, with caps on each issuer's weighting to limit concentration in any single company, and the index is rebalanced monthly.

• Abundant liquidity within the investment grade corporate bond category
• Diversification through issuer weight caps

Assets under management (AUM) stand at $32.0B, and the total expense ratio is 0.14% per year.

Its fees are somewhat higher than those of lower-cost substitutes in the same category, but it holds an edge in trading liquidity and name recognition.

Investment grade corporate bond prices move with the direction of market interest rates and changes in credit spreads, and during periods of rate volatility they have shown price swings proportional to duration. Coupon income forms the foundation of total return.

Flows have been fairly steady, driven by demand for core bond holdings and stable income, and when expectations of rate cuts grow, inflows into bond ETFs as a whole have sometimes been observed.

Its strengths are abundant liquidity and diversification in investment grade corporate bonds, while its weaknesses are interest rate sensitivity and credit risk.

USIG, shown in the table, is an investment grade corporate bond ETF with a wider maturity range and a lower expense ratio, making it a direct substitute. USHY, HYG, JNK, and SPHY are high yield corporate bond ETFs that aim for higher returns but carry greater credit risk. If you want broad aggregate bond exposure that includes corporate bonds, you can also consider AGG and BND, and to reduce credit risk, GOVT, which focuses on US Treasuries.

Here are the points to review before investing in LQD. Although it is a core bond asset, interest rate sensitivity, the credit environment, and exchange rates should be checked in advance. Expense ratio and duration levels affect long-term returns, so it is wise to review them together.

Rising interest rates and wider credit spreads are the main drivers of short-term price volatility. Even investment grade bonds can decline in price during economic shocks, so duration and the credit environment should be reviewed together.

It is a standard choice as a core bond asset diversified across investment grade corporate bonds. To lower costs further, a lower-fee corporate bond ETF such as USIG could be an alternative, and for aggregate bond exposure, aggregate bond ETFs such as AGG and BND are options.