You cannot use the standard copy-and-paste techniques to copy a summary of subtotals.
Select the cells to copy. Be sure that the rows of data are hidden and that only the subtotals are visible.
Select a cell in the data region, Right Click->Copy .
Hit <F5> or <Ctrl G> or Edit -> Go to -> Special -> Visible Cells Only Click OK.
Copy and Paste the summary of the Subtotals into a different sheet. Only the values of the data are pasted.