A scuba diver dove from the surface of the ocean to an elevation of −49 9/10 feet at a rate of −11.1 feet per minute. After spending 14.75 minutes at that elevation, the diver ascended to an elevation of −18 9/10 feet. The total time for the dive so far was 21 1/8minutes. What was the rate of change in the diver's elevation during the ascent? Round your answer to the nearest hundredth.