Before 2007, the wt taught that the 144,000 had been "sealed" in 1935. If this had been the case, then the number of anointed left on earth would have continually declined. But that hasn't happened. So:
- 2007 - we can not know when the calling of the 144,000 ends.
*** w07 5/1 p. 31 Questions From Readers ***
"it appears that we cannot set a specific date for when the calling of Christians to the heavenly hope ends."
(This change was clearly a reaction by the wtbts to the highly inconvenient increase in the number of partakers.)
A further "refinement in understanding" came in 2011.
- 2011 - it's not important to know how many anointed are left on earth;
and, a related refinement from the same article:
- 2011 - some memorial partakers have a "mental or emotional imbalance" and thus are mistaken
*** w11 8/15 p. 22 Questions From Readers ***
A number of factors—including past religious beliefs or even mental or emotional imbalance—might cause some to assume mistakenly that they have the heavenly calling. We thus have no way of knowing the exact number of anointed ones on earth; nor do we need to know.