"In Genesis 15:5, the Bible said that Abraham would have many descendants and that counting them would be like counting the stars. Today, scientists say it is impossible to count the stars because the universe is too vast. Today, we also know that counting Abraham's descendants is also impossible. There are about 20 million Jews in the world today."20 mil / 6.5 bil = 0.31% of the world, or less than one-third of 1%.
... and I rounded up.