moderate - Trading volumes correlate with equity market participation and retail investor confidence, which rise during economic expansions. However, volatility during downturns can offset volume declines with higher options trading. Customer equity balances (and thus margin lending revenue) are procyclical, declining 20-30% during bear markets. Net new account growth accelerates during bull markets when retail FOMO peaks.

extreme positive sensitivity - Net interest income represents 55-65% of revenue and scales linearly with short-term rates. Each 25bp Fed funds increase adds $110M+ annual revenue (assuming $110B customer cash × 0.25% spread capture). The company maintains minimal duration risk by investing in overnight/short-term instruments. Rising rates also compress equity valuations broadly, but IBKR's earnings growth from NII expansion typically outweighs multiple compression. Zero debt means no financing cost headwinds.

growth - Investors buy IBKR for secular growth in global retail trading participation, market share gains from incumbents, and operating leverage as scale increases. However, stock also attracts rate-sensitive investors during hiking cycles due to NII sensitivity. 27.4% EPS growth and 6.7% FCF yield appeal to GARP (growth at reasonable price) investors. Minimal dividend (most cash retained for regulatory capital) makes it less attractive to income investors.