some polls add up to 99%

some of the polls (noticed this on 2 occasions) add up to 99% instead of 100% i haven't however noticed a pattern so this will probably be limited help...
but not all are wrong!...

see (for examples):
Again, best hard drive maker?
(albeit it's an old but (seemed at least) active)

buy it or build it?
95+4 does not equal 100....

Edit: ok, i found the problem... the 4% (when i checked on the second link) was 4.76% and was rounded down and/or ignored

Ara

yeah... ok, it's not a big thing, but it just doesn't look right...

Ara