Sparse Rho

Key _Sparse Rho in Vol Curve refers to the table with the calibrated SABR Rho parameters, represented as an object of type Table2D
It contains the same numerical values as those in _Sparse SABR Params in the column under the title #Rho

Note, this is generated as soon as the contents of a Vol Curve object are displayed.
For efficiency reasons this is never generated during the creation of a Vol Curve object as long as the object's contents are not displayed.

Note this key is prefixed by _, which indicates it is regarded as a read-only part of the object's data and therefore its associated value cannot be edited.
For that reason it does not appear as part of the input data.
It carries informational only value for the user and appears as part of its contents.
Also it completely depends on the remaining object contents and therefore is never part of the exported object's data.