Only 3% of the world’s population is at least 6-feet tall, according to online data. In the United States, just 14.5% of men and less than 1% of women reach that height. An even smaller percentage — 3% to 6% of adults in the U.S. — weigh at least 300 pounds. At 6-foot-8 and 322 pounds — he’s slimmed down since his high school and early college days — Mount Airy native Rob Havenstein checks ...