just i send a example for box office collection,how they made.That is not 100% true,but they are giving some assumption.
I budget is 92 c only but 10 extra,yennai arinthal collected 74 C but here he put 97.5.Kakki sattai collected only 46 C but here 13 extra.
Hit is calculating by the Hit=production cost - distributor share - tax.For 'I' movie the share is high but film got to failed to achieve.Yennai arinthal also share is high that is the reason film got failed to fill the distributors pockets.
All time top ten movies in world highest grosser:-
1.Endhiran
2.I
3.Vishwaroopam
4.Thuppakki
5.Dhasavatharam
6.Kathi
7.Linga
8.Singam 2
9.Sivaji
10.Arambam