Baseball equipment maker We're Bats identifies a number of market segments, including "Diamond Tykes"$--$families with very young players. We're Bats tries to appeal to this segment by focusing on fun. Last period, We're Bats sold $$90\mathrm{.}9$ million in baseball equipment, in a market with $60\mathrm{.}6$ million potential customers. Out of their total sales, We're Bats estimates that it sold $$17\mathrm{.}7$ million in equipment to Diamond Tykes, a segment that may include $6\mathrm{.}7$ million potential customers. Calculate We're Bats' brand development index for the Diamond Tykes segment. Report your answer as a percent. Round to the nearest tenth of a percent. Report $25\mathrm{.}5\%,$ for example, as $"25\mathrm{.}5".$