It's complex algorithm, where the absolute value of all dollars accrued by each individual at the end of the month are tabulated then summed to form an aggregate value on an individual by individual basis. Then the values obtained for all individuals are sorted with the highest and lowest values representing the extremes. These are then indexed numerically with the highest individual value receiving the lowest index. The results of this index are then published as a rank.

why this month the all time ranking doesn't changed??????

Glad you asked! Again, it’s complicated. You need to take in the factors mentioned above and then bound them by measurements made in the conventional 4th dimension. If you assume a finite boundary on the past event horizon, say one limited to events occurring in the last few days, obviously, the results (in this case ‘rankings) will become more stochastic and one would expect month to month fluctuations. However, if you take an infinite horizon, such as one implied by ‘all time’ small temporal variations become less significant. If ranking were thought of as the integration of rate of accrual over time…well, you get the idea. The result is that the data become very resistant to small perturbations and the rankings stabilize. Thus, to use your terminology, they doesn’t change.

no no.... it doesn't changed!! it is identical to the last month!!!! ALL 500 ranking! identical! it is not possible..

and the name of the table?? with which criterion they have been name this month? it not is names of top of month.
(sorry my english, i don't speack well)

This is of course off topic, but seems like as good a place as any.

http://aplayr.com/?name=winnersfinal

Even further of topic ...

Moo!?

Only thing noddin didn't mention is... if a spade comes on the river -- well it all goes out the window then.