A death cross is seen when the short-term moving average of a security or index falls below its long-term moving average.Consider the recent performance of Conglomo’s stock. After both its 50-day and 100-day moving averages ascended for several months, its 50-day average crossed below the 100-day average shortly after the stock reached its peak value. Both trends descended from there, and the long-term average became the new resistance level. Technical traders who study a stock’s historical values to predict its future direction will interpret a death cross as a bearish signal marking the time to sell. They’ll believe a short-term decline is becoming a long-term trend. But that’s not always the case, and investors should not base their decisions on a single indicator. Other time frames used when looking for crossovers include the 10-day to the 50-day moving average, and the 50-day to the 200-day. Longer-term indicators usually carry more weight.