This is a comparison of sales for stores that have been open for business for at least 12 months, expressed as a percentage.
Comparable store sales growth is often called "comp store sales", "comps" and "same store sales". Comparable store sales growth signals the productivity in sales of a preexisting store or restaurant compared to the previous year.
This metric is used to determine what amount of new sales comes from actual sales growth or merely comes from new store openings. If comparable store sales growth is stagnant, but overall revenue growth is increasing for example, the revenue growth can be attributed to new store openings instead of actual store productivity.
Furthermore, declining same store sales growth may merely be a function of dropping sales company-wide, but may also mean that the company's new stores are cannibalizing sales from its preexisting locations.