MaxBarsBack

Trading strategies frequently need a certain number of bars of data before they can start performing calculations. This waiting period can be adjusted and it is called Maximum number of bars a study will reference, or MaxBarsBack. For example, a 60-bar moving average would require a MaxBarsBack setting of 60 to begin calculating, which is 59 historical bars and the current bar.  

The default MaxBarsBack for a strategy is 50 bars and must be manually changed if a strategy requires more data history by changing the Maximum number of bars study will reference setting that is accessed by clicking Properties for All from the Strategies tab of the Format Analysis Techniques &  Strategies dialog.