English: North Atlantic Tropical Cyclone Activity According to the Accumulated Cyclone Energy Index, 1950–2015. This figure shows total annual Accumulated Cyclone Energy (ACE) Index values, which account for cyclone strength, duration, and frequency, from 1950 through 2015. The National Oceanic and Atmospheric Administration has defined “near normal,” “above normal,” and “below normal” ranges based on the distribution of ACE Index values over the 30 years from 1981 to 2010. Data source: NOAA, 2016 http://www.aoml.noaa.gov/hrd/hurdat/comparison_table.html