Liquidity dynamics across small and large firms

In this paper, we analyse cross-sectional heterogeneity in the time-series variation of liquidity in equity markets. Our analysis uses a broad timeseries and cross-section of liquidity data. We find that average daily changes in liquidity exhibit significant heterogeneity in the cross-section; the liquidity of small firms varies more on a daily basis than that of large firms. A steady increase in aggregate market liquidity over the past decade is more strongly manifest in large firms than in small firms. Absolute stock returns are an important determinant of liquidity. We investigate cross-sectional differences in the resilience of a firm's liquidity to information shocks. We use the sensitivity of stock liquidity to absolute stock returns as an inverse measure of this resilience, and find that the measure exhibits considerable cross-sectional variation. Firm size, return volatility, institutional holdings, and volume are all significant cross-sectional determinants of this measure. © Banca Monte die Paschi di Siena SpA, 2004.