Due to the use of averages, and statistics estimated in part, the number itself is obviously not perfectly accurate, but is pretty close. There is some evidence also that the rate of induced abortions has dropped slightly in the U.S. since 1999, however, the U.S. (according to the same report) accounts for less than 5% of worldwide abortions (and therefore less than 23% of abortions in developed nations), and so the difference would be minimal to an already approximated number. There could be more abortions, there could be less. But basically, the counter is sadly roughly accurate.
Note: On the links with “not recommended for ages under 12” it’s not that they are bad websites, on the contrary those sites are excellent. It is just that there are pictures of the aborted babies and also there is a video of an ultrasound that shows an abortion from the victim’s position.