I found a
similar survey for the UK, although the numbers are arranged differently.
Adjusting for the way the numbers are done:
25% haven't read a book in the past year
10% have read 1 or 2
18% have read 3 to 5
15% have read 6 to 10
15% have read 11 to 20
15% have read more than 20
2% don't know.
So the UK median is 3-5 books, towards the top of that range.
The UK figures do give more detail at the high end. Only 4% of people read more than 50 books a year.
The figures are remarkably similar, UK and USA.