In Excel, it is not uncommon for the user to call a function that should return a number, and find that the resulting value looks like a date or a time (eg. "01/01/1900", "02:00:00"), instead of an integer or floating point number.
This problem usually occurs because the cell containing your formula is formatted as a 'date' or 'time' instead of a 'General' type or a number.
This is often because you have inserted a new column, next to a column containing Dates or Times, the new column has 'inherited' the formatting of the adjacent column.
As Excel internally stores dates and times as numbers, the Excel 'date' format will cause a cell to display a simple number as a date, and the Excel 'time' format will cause a cell to display a simple number as a time. Note that it is only the cell formatting that is 'wrong' in this example, NOT the value returned by the function.
This problem is easily solved, by altering the cell formatting. This is done by the following simple steps: