Go to the Engagement > Events report and select ‘Last 30 days’ from the date picker.
Make note of the total page_view event count here, we’ll use it to calculate the percentage later.
Click the plus sign (+) next to ‘Event name’ to add a secondary dimension of ‘Country’.
If it doesn’t load at the top, you can search for ‘United States’ to narrow down the results.
Now you just need to take the event count shown here for United States pageviews and divide it by the total event count we saw earlier. In this example: 81,837 / 93,939 = 87% US pageviews.