The answer is none. The Travel Separation package is a resignation from the company. If someone is eligible for retirement there is no reason whatsoever to take the travel separation package.
By the way, you were evidently counting the Retirement Roster. That will not tell you how many retirees there are in a given month. That will only tell you how many retirees gave the company permission to post their names and info.
As a matter of fact there was a total of 16 retirees in January.
Thanks for the clarification Jim.