How rare?

The 99th percentile for the height of adult USA males might be 6' 3 5/8" (192 cm). So if you're 6' 4" tall, you're taller than 99% of other adult males.

If you're 200 cm tall (6' 6 3/4"), then you're taller than 99.98% of other adult males.

If you're 205 cm tall (6' 8 5/8") like me, then you're taller than at least 99.999% of other adult males. Among the US population, you are taller than all but about 7,000 other adult men.

Which is why, in my life, I have only met 2 people who were taller than me. And one of them was Robert Parrish.