Formatting Subtotals

[Guest]

When using Data, Subtotals to create subtotals in a detailed spreadsheet,
how do I set the format so that all subtotal lines are bolded and are
followed by a specified number of blank rows?

 

[Guest]

One option -

Collapse the sheet to show only the subtotals, then select visible cells
only (F5>Special>Visible Cells only)

Then Bold those cells and, instead of adding empty rows, make the subtotal
rows taller and format them with the vertical alignment at the top