Chrome has an internal page that shows the amount of data transferred this session and the total amount of data transferred ever since this feature was added or you first used Chrome. Just open a new tab, paste this in the address bar: chrome://net-internals/#bandwidth and then press Enter.
Check the Original (KB) row of the table, where you can find bandwidth consumption data in kilobytes. For example, I used 40,024.5 KB since launching Chrome. The Savings values are only useful in the mobile Chrome for Android and iOS if the data saving proxy is enabled.
Savings = Original - Received