This paper uses quarterly U.S. data from 1953(6) to 2000(6) to investigate the effects of share-price changes on investment. We focus on the distinction between speculative and fundamental components of share-price movements and we contribute to the literature by evaluating four alternative methods of decomposing share-price movements into these two components. The four methods are: (1) a decomposition based on regressing share returns on a set of variables designed to capture fundamentals; (2) the use of the price-earnings ratio; (3) the use of the dividend yield and (4) a structural vector-autoregressive model based on the dividend-discount equation. We find that, no matter what the method of decomposition is, shocks to both fundamental a...