FORMULATEXT Returns the formula at the given reference as text
IFNA Returns the value you specify if the expressions resovles to #N/A, oherwise returns the result of the expression
PDURATION Returns the number of periods required by an investment to reach a specified value
PRI Returns an equivalent interest rate for the growth of an investment
XOR Returns a logical expression OR of all arguments
DAYS Returns the number of days between 2 dates
ISFORMULA Returns TRUE if there is a reference to a cell that contains a formula