A historic record of the performance of a business listing all the gains/revenues/profits etc and deducting all the losses, costs and expenses to arrive at a 'net' Profit or Loss position for the historic period under review. It's a past summary of business performance detailing exactly how the net result was achieved.
A statement - with lots of numbers in it - outlining the PAST achievement of a business. Its sole purpose is to explain as clearly as possible what the financial business performance was. The apparently confusing terminology is not deliberate, but there to describe the exact set of circumstances of a complex living business.