This function is only available when connected to a Teradata database.
An enhanced version of the standard correlation function is supported, generating CORR(expression1, expression2) and returning a value of type float. When dragging a Correlation into a variable, the following tree element is created.
Variable Creation > Input > Variables: SQL Elements pane - Aggregation > Correlation

Columns and/or other non-aggregate expressions can be moved over the two (empty) branches of the tree.
The enhancement is the ability to compute the correlation when either or both the first and second expression arguments evaluate to type date, generating one of the following:
CORR(date expression1 - DATE '1900-01-01', expression2) CORR(expression1, date expression2 - DATE '1900-01-01') CORR(date expression1 - DATE '1900-01-01', date expression2 - DATE '1900-01-01')
There are no special properties for the Correlation function.