Annual fund cost

The yearly fee deducted from fund assets, expressed as a percentage. SPY charges 0.09%; an actively managed ETF might charge 0.75%. A seemingly small difference compounds significantly over decades — a 1% fee on a $100k portfolio costs over $30k over 30 years.

True per-share value

Net Asset Value is the per-share value of the fund's actual holdings. ETF market prices stay very close to NAV because authorized participants arbitrage away any gap. A premium means the ETF trades above its holdings' value; a discount means below.

Benchmark deviation

How closely an ETF follows its benchmark index over time. Differences arise from fees, dividend reinvestment timing, and sampling. Lower tracking error is better for passive investors — it means you're getting what the index delivered, minus costs.

Hidden trading cost

The difference between what buyers pay and sellers receive. For liquid ETFs like SPY, the spread is fractions of a cent. For thinly traded ETFs it can be 0.5% or more — a cost paid on every trade. Use limit orders to avoid paying the full spread.

Income paid out

The income (dividends, interest) distributed to shareholders, expressed as an annualized percentage of price. Bond ETFs like AGG pay monthly; equity ETFs like SPY pay quarterly. Distributions are taxable in non-retirement accounts even if you reinvest them.