Further evidence of the November effect

Tax-loss selling by individuals has long been thought to be a major factor driving the January effect. The Tax Reform Act of 1986 changed the tax-year end for mutual funds to October 31 and increased the marginal tax rate, creating a natural experiment allowing Bhabra, Dhillon, and Ramirez (1999) to empirically test the tax-selling hypothesis. They find empirical support for a postact November effect. However, a second paper by Gibson, Safieddine, and Titman (2000) finds empirical support for the November effect in only one post-act year, 1990. In this article, we respecify betas, calculate holding period returns over each tax year, construct portfolios with large, differences in mutual fund ownership, and test for the presence of a bid-ask spread bias. The empirical results offer evidence of a November effect but only in the first week of November.