Hello student, 

It's difficult to give the exact number of students who have qualified the competitive exam and secured a rank below 1000 AIR. But still 40% students would be there who would have cracked it without taking coaching. The thing you should only study is NCERT and then some of the competitive level books to solve problems.

Hello aspirant! Let me to inform you that this is a question that can not be answered exactly since jee doesn't reveal such personal details .However on a rough note there are very few students to get rank under 1000 without any coaching. You can qualify and get good rank without coaching but under 1000 is very difficult.