नहीं कोई गम, रेलवे से हैं हम - Aman

Here are the rules about Tatkal issued in 2009. If there have been any changes please advise source:
Instead of full coach being presently nominated as Tatkal Coach, there will be Tatkal quota in each train in 2A, 3A, AC Chair Car, Sleeper and 2S (Second Sitting) classes as under:-
Classes No. of berths to be earmarked in trains with average occupancy level of Tatkal Quota
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Less than 80% More than 80%
2 AC 4 Berths Per Coach 10 Berths Per Coach
3 AC 6 Berths Per Coach 16 Berths Per Coach
AC Chair Car 6 Seats Per Coach 16 Seats Per Coach
SL 10% of the accommodation or one coach whichever is less 30% of the accommodation
Reserved Second Sitting (2S) 10% of the accommodation
In those trains and classes where average utilization of Tatkal accommodation during six months period i, e April to September is 80% and above, tatkal charges applicable during peak period will be charged through out the year i.e for both peak and non peak period.
There will be no separate Tatkal train defined. The unutilised Tatkal quota will get released to waitlisted passengers.