The sales page shows overall sales data for all or individual markets.
Clicking on the Earth Icon, you get to choose to switch to an individual market. Once you select an individual market, it's going to reflect on all the other analysis tabs under the sales page.
The last updated XX minutes ago shows when was the last time the system had crunched your data.
Each card shows your overall sales separated into Daily, Weekly, Monthly, and Yearly, It also shows your average sales in each timeframe, the previous timeframe sales, the current time frame sales, and the changes from the previous timeframe sales.