What,, only 20 ??? not very many, and I do believe the speed is highly exaggerated. 50,000 MPH is a statistically fast one.
Sure, one big enough to be a global killer making impact would be araggedon, but we find those a long way out and can moddle their path. To date, nothing so close to be any threat at all.
Look how many just this year, most people never were aware of. A couple months ago, a rogue asteroid zipped past earth, not even spotted until it was closer than the moon, big enough to wipe out a city had it hit.
These have been going on since time began, surely you heard about the one over Russia, far from global, but a lot of broken windows.
Best I can say, don't worry about it.