In this screenshot of the APM Transactions view from New Relic's online help,
What does the shaded are that I have circled in red ink indicate? I've been unable to find this in their documentation. (In this specific case, the top transaction's entire bar is shaded, but this is not always the case in my production environment)
shaded area = progress bar, it's a UI feature that display the time as a percent based of the max time display, meaning first row consider as 100% and each row "progress bar" is calculated accordingly
It helps to visualize the difference between rows
In your case 7.78 is 100% and other rows are shown the progress bar as percentage of 7.78.