Markets can move only if enough new losers enter the game to supply profits to winners. If the market is falling, it takes a very courageous or reckless bull to step in and buy, but without him there is no increase in volume. When the trend is up, it takes a very brave or reckless bear to step in and sell. Rising volume shows that losers are continuing to come in, allowing the trend to continue. When losers start abandoning the market, volume falls, and the trend runs out of steam. Volume gives traders several useful clues.
