Net sales of tailored brands increased 4.5 per cent to $818.0 million in the first quarter of fiscal 2018. Retail net sales went up by 4.1 per cent while retail segment comparable sales grew by 2.1 per cent. Corporate apparel net sales increased by 9.6 per cent, or $5.5 million, due to the impact of a stronger British pound this year compared to last year.
On a GAAP basis, consolidated gross margin was $345.2 million, an increase of $12.8 million, primarily due to the increase in net sales. As a percent of sales, consolidated gross margin decreased to 42.2 per cent. On an adjusted basis, consolidated gross margin decreased 40 basis points, primarily due to a decrease in retail gross margin rate.
On a GAAP basis, retail gross margin was $328.8 million, an increase of $12.1 million. As a per cent of sales, retail gross margin lowered to 43.6 per cent. On an adjusted basis, retail gross margin increased $10.7 million while the retail gross margin rate decreased 30 basis points primarily due to increased promotional activities, mostly offset by lower occupancy costs as a percent of sales.