Catria

Depends on the subject, it tells you what year on the top of the page of rankings though (like Computer Science, Ranked in 2014). 

Also, amusing? USNews mirrors most international ratings and schools obviously put enough stock into it to post USNews rankings on the program page.

Physics is also a subject ranked in 2014. Only my question is: when will it be ranked next?

Usually November I believe, but it doesn't matter as the rankings don't change drastically throughout each year (a professor at CMU wrote about getting into PhD CS, he said when speaking about USNews ranks... "Note that the top 4 schools in this list have been fixed since the time I applied for graduate school, over 20 years ago.") .