The Excel SHEET function returns the index number of a sheet in Excel. It will report the sheet number for a cell reference, named range, or Excel Table.
Syntax:= SHEET ([value])
The SHEET function syntax has the following arguments:
 Value Optional. Value is the name of a sheet or a reference for which you want the sheet number. If value is omitted, SHEET returns the number of the sheet that contains the function.
Example: Let’s look at some Excel SHEET function examples and explore how to use the SHEET function as a worksheet function in Microsoft Excel:
Syntax: =SHEET(Cost!A2)
Result:
Based on the Excel spreadsheet above, the following SHEET examples would return:
Syntax: =SHEET(Cost!A3)
Result: 2
Syntax: =SHEET(Cost!A4)
Result: 2
Syntax: =SHEET(sophuc.com!A5)
Result: 1
Syntax: =SHEET()
Result: 1
Syntax: =SHEET(Year!A7)
Result: 3
Syntax: =SHEET(Year!B8)
Result: 3
Syntax: =SHEET(Sheet1!C9)
Result: 4
Note:

SHEET includes all worksheets (visible, hidden, or very hidden) in addition to all other sheet types (macro, chart, or dialog sheets).
 If the value argument is not a valid value, SHEET returns the #REF! error value. For example, =SHEET(Sheet1!#REF) will return the #REF! error value.
 If the value argument is a sheet name that is not valid, SHEET returns the #NA error value. For example =SHEET(“badSheetName”) will return the #NA error value.

SHEET is not available in the Object Model (OM) because the Object Model already includes similar functionality.