I'd point out that one would expect the SSA tables to overstate the number of centenarians etc, for the simple reason that they are linked to financial payments/checks. Japan recently had some interesting reports that its centenarian numbers were overstated... because other people were collecting their pension checks. From the BBC:

More than 230,000 elderly people in Japan who are listed as being aged 100 or over are unaccounted for, officials said following a nationwide inquiry. An audit of family registries was launched last month after the remains of the man thought to be Tokyo's oldest were found at his family home. Relatives are accused of fraudulently receiving his pension for decades...Reports said he had received about 9.5m yen ($109,000; £70,000) in pension payments since his wife's death six years ago, and some of the money had been withdrawn.

...Officials have found that hundreds of the missing would be at least 150 years old if still alive.