Oracle SQL: NORMDIST Function for creating Bell Curve Charts

I had been scouring the web for a solution to find some sort of function to produce the same result as the NORMDIST Excel produces with no luck.

Therefore after decoding Microsoft's miniature equation in their help file,



I have created the below function. 

create or replace FUNCTION "NORMDIST"(

      x_VAL IN number,

      x_Mean IN number,

      x_STDEV IN number

      )

    RETURN number

  IS

    NDIST number;

  BEGIN

    

    NDIST := round((1/(sqrt(asin(1)*4)*X_STDEV))*exp(-((power((X_VAL-X_MEAN),2))/(2*power(X_STDEV,2)))),14);

    RETURN (NDIST);

    

  EXCEPTION

  WHEN OTHERS THEN

    RETURN NULL;

  END;

The function should produce the same outcome as "=NORMDIST(Val, Mean, Stdev, False)" in Excel. I don't have a degree in maths, but after testing the code it works and displays the same results. Hope it helps.