They sold 4,000 Mazda 3's and over 10,000 CX-5s last month. How is that pretty close?
The Mazda 3 and Mazda 6 sales have been dropping by every month and they will only sell ~70,000 Mazda 3's this year. Car sales in the USA are crashing.
Car sales in general are sliding as people buy crossovers - probably the 3's biggest competitor is indeed the CX-5, but also the new Civic which appears to be crushing the segment in sales. The current 3 is due for a refresh - looks like the 2019 MY for it.