The best moving average crossover combination depends on the time horizon of the trader, as well as the market being traded. A short time horizon calls for a moving average crossover strategy that uses shorter moving averages, such as the 5 period and 20 period. A longer time horizon might see a trader using a crossover strategy that combines the 50 period and 200 period moving averages. Using both combinations together can yield the best strategy. The trader uses the long time horizon to determine the longer-term trend, and then only trades in that direction using signals generated by the shorter-term strategy.