IFERROR Evaluates an expression and returns a specified value if the expression returns an error; otherwise returns the value of the expression itself.
Syntax
IFERROR(value, value_if_error)
Parameters
Value – Any value or expression.
Value_if_error – Any value or expression.
Return Value
A scalar of the same type as value
Reference Data
https://docs.microsoft.com/en-us/dax/dax-function-reference