Use the "Show Walking Analysis" menu item in the View menu to open the report. Your report window will open;

Data may take time to load so the numbers will appear as the data is loaded.
See a video here.
You can also see the source data for this report by opening the Measurements window (from the main menu window, click the measurements icon). This will show the window below. You can select any category and then a data type in that category to see the entries you have stored for that data type. You can add data manually if you have data from sources other than your iPhone.
Currently the chart function is basic and may contain errors. Look for improved charts soon.