Fast Casting

Fast casting reduces the amount of time required for casting spells according to the following formula: (Cast time) = (base time) * 2^(-attribute/15)

Because of the severe diminshing returns, the "sweet spot" is 7-9 points total in Fast Casting. 7 points reduces by 28% the amount of time required to cast a spell, while 9 seconds takes 33% off.

Below are tables listing the cast times of spells in ascending order from one to five seconds. The times in this table are rounded to the nearest 1/100th of a second, however it is unknown where Guild Wars does it's rounding.

One Second
Fast Cast Time 0	1.00 1	0.95 2	0.91 3	0.87 4	0.83 5	0.79 6	0.76 7	0.72 8	0.69 9	0.66 10	0.63 11	0.60 12	0.57 13	0.55 14	0.52 15	0.50 16	0.48

Two Seconds
Fast Cast Time 0	2.00 1	1.91 2	1.82 3	1.74 4	1.66 5	1.59 6	1.52 7	1.45 8	1.38 9	1.32 10	1.26 11	1.20 12	1.15 13	1.10 14	1.05 15	1.00 16	0.95

Three Seconds
Fast Cast Time 0	3.00 1	2.86 2	2.74 3	2.61 4	2.49 5	2.38 6	2.27 7	2.17 8	2.07 9	1.98 10	1.89 11	1.80 12	1.72 13	1.65 14	1.57 15	1.50 16	1.43

Four Seconds
Fast Cast Time 0	4.00 1	3.82 2	3.65 3	3.48 4	3.32 5	3.17 6	3.03 7	2.89 8	2.76 9	2.64 10	2.52 11	2.41 12	2.30 13	2.19 14	2.09 15	2.00 16	1.91

Five Seconds
Fast Cast Time 0	5.00 1	4.77 2	4.56 3	4.35 4	4.16 5	3.97 6	3.79 7	3.62 8	3.45 9	3.30 10	3.15 11	3.01 12	2.87 13	2.74 14	2.62 15	2.50 16	2.39