magento-test/app/code/Magento/Reports

Magento_Reports module provides ability to collect various reports such as:

• products reports (bestsellers, low stock, most viewed, products ordered),
• sales reports (orders, tax, invoiced, shipping, refunds, coupons, and PayPal settlement reports),
• customer reports (new accounts, customer by order totals, customers by number of orders),
• shopping cart reports (products in cart, abandoned carts)