In this paper, the relation between the signs of recent returns (an up-down pattern) and the net trading of individual investors is studied. Using our comprehensive dataset from the Taiwan Stock Exchange, we find that following positive days, individual investors sell more stocks than they buy — a negative buy-sell imbalance — while following negative days, this imbalance is positive. The signs of more recent returns have stronger impacts on imbalance. The subsequent performance of this trading behavior is poor, indicating that individual investors in Taiwan make suboptimal decisions, and they are unlikely to make information-based trades. Thus, the liquidity provision explanation in the literature is not applicable to our sample.