I was just checking registered sex offenders in Alaska and we have 3434 listed and with a population of less than 600,000 that is more than 4%.
4% of 600,000 is 24,000. 1% of 600,000 is 6,000, in other words, Alaska's rate is a little over 1/2 of 1%. I think you got closer to 640,000 residents btw.