The table has two rows, New Customers and Repeat Customers, each with its % of Total Invoices, Invoice Count and Average Ticket. An invoice counts as New Customers when it is that customer's first ever finalized invoice at your store, looking back over the store's whole history in ARM, not just the dates you chose. Every later invoice for the same customer counts as Repeat Customers. Quick sales are left out, because they carry no customer. Average Ticket is the invoices' gross sales, including sales tax, divided by the number of invoices.
Under the table, Invoices Reviewed counts every invoice finalized in the period, Quicksales Excluded is the number of quick sales taken out, and Total Invoices Reviewed is what is left, the invoices the table is based on.
The printout is headed New vs Repeat Customers with the dates you ran, and shows the same table and counts.
A customer whose earlier visits happened before the store started using ARM counts as new on their first invoice in ARM. An invoice finalized without a customer, other than a quick sale, is counted in Total Invoices Reviewed but in neither row. For how coupons perform with first-time and repeat users, run Coupon Analysis Report.