The number of people visiting a shop or a chain of shops in a period of time is called its footfall.
Footfall is an important indicator of how successfully a company's marketing, brand and format are bring people into its shops.
Footfall is an indicator of the reach a retailer has, but footfall needs to be converted into sales and this is not guaranteed to happen. Many retailers have struggled to turn high footfall into sales.
Trends in footfall do tell investors something useful. They may be an indicator of growth and help investors to understand why a retailer's sales growth (or decline) is happening. Investors may want to know whether sales growth due to an increase in the number of people entering the shops (footfall) or more success at turning visitors into buyers (which can be seen by comparing footfall to the number of transactions).
Sales growth may also come from selling more items to each buyer (compare number of transactions to sales volumes), selling more expensive items (an improvement in the sales mix), or increasing prices. Which of these numbers is disclosed varies from company to company. Investors should look at whatever is available.