Food-on-the-go chain Pret A Manger has hiked sales by 14% to £676.2m in 2015 thanks to increased demand for healthy and vegetarian products, with five million avocados eaten by customers.

Global revenues increased by 7.5% on a like-for-like basis – stripping out the 36 new stores opening in the year – and helped EBITDA rise 14.5% to £84.3m.

Of the 36 new shops opened in the 12 months to 31 December 2015, 23 were in the UK, with 12 outside of London.

Pret said it was continuing to adapt its UK menu to meet growing demand for healthy options, with 14% of total sales coming from food and drink items introduced in the past year. The chain also experienced increasing interest in vegetarian products, which registered double-digit growth.

New ranges include its grain-based ‘SuperBowl’ salads, with 17,000 of the beets, squash & feta mal sold every week – out-performing chicken and salmon options. Avocado was the fastest-growing ingredient for Pret, with customers eating five million in total.

Sales outside of the traditional lunchtime period also rose to account for 58% of the total as a result of increased demand for breakfast on-the-go.

The chain added that 65% of all its UK card payments were now contactless.

Pret CEO Clive Schlee said: “Last year thousands of customers told us they were trying to eat less meat. This year we have challenged ourselves to increase our vegetarian options in all shops, as well as opening a veggie-only pop-up shop to learn more from our customers.”

The US was Pret’s fastest growing market last year, achieving 13.8% like-for-like sales growth, driven, the chain said, as a result of improvements in the quality of ingredients and innovation in salads and breakfast items. Opening larger shops in prime locations also helped grow sales.

“These results represent another year of record sales for Pret,” Schlee said. “The highlights were a strong performance in the US – our newly opened Penn Station shop has the highest sales per square foot of any Pret in the world – and the opening of two very busy transport hub shops in Paris’ Gare de Lyon station and Nice Airport. Pret continues to grow steadily in the UK, adapting its menu to meet demand for healthy options.”