To add the DO EVERY PERIOD query block, select Tools>Add Query Block>Do Every Period from the menu bar.

Example Query:

The following query generates an analog chart. The OLD symbol is the historical one, the @ is the instrument you are interested in. In this example they are the same but it does not always have to be the same (for instance you could compare the current stock market against soybeans). The CorTimePeriod is the look-back window for the correlated history search. If CorTimePeriod is set to 100, for example, it looks back at the last 100 days of history in the @ ticker and searches the Old ticker for 100-day periods whose coefficient of correlation is strongest, meaning that the movements are closest to the current periods.

%graph.plot.colors:  "black blue red green yellow cyan blue magenta orange pink"
%graph.back.color:  "white"
%graph.scalewith: "@" "@"
%graph.scalewith: "Old" "Old"


   LET 
     Old = SPX
     @ = SPX
     ATTR CorTimePeriod = 100 
     ATTR StartYear = 1950 

   INITIALIZE 
       daysAgo = 0 
     AND 
       beginDate = construct_date ( 1, 1, StartYear ) 
     AND 
       BestValue = 0 
     AND 
       BestDate = 0 
   LET 
     ATTR iteration = 1, 2 

   DO EVERY 1 day 
       iteration is exactly 1 
     AND 
       Old CorTimePeriod days ago  is DEFINED 
     AND 
       Date is after 1 day before  date:beginDate 
     AND 
       Date is before CorTimePeriod days before  Old  last_data_day 
     AND 
       thatMany = periods_in_range from today to Old  last_data_day  
     AND 
       thisCor = correlation ( Old, @ thatMany days later, CorTimePeriod days
        ) 
     AND 
       IF 
         thisCor is more than BestValue 
         THEN 
           BestDate = current date 
         AND 
           BestValue = thisCor 
       ENDIF 

   SHOW 
     {
       Old: BAR of Old 
       @: BAR of @ thatMany days later  
       Correlation: IF 
                        Old thatMany days later  is DEFINED 
                    THEN correlation ( Old, @ thatMany days later, 
                         CorTimePeriod days ) 
                    ENDIF  
     } 
       repeated from CorTimePeriod units ago  to CorTimePeriod units later  
   WHEN 
       iteration is exactly 2 
     AND 
       Date is after 1 day before  date:beginDate 
     AND 
       Date is date:BestDate 
     AND 
       thatMany = periods_in_range from today to Old  last_data_day  

In the resulting chart, the correlation value is plotted in the lower pane.