The table on the right shows the ACE for each storm in the season. Broadly speaking, the ACE is a measure of the power of a typhoon multiplied by the length of time it existed, so storms that last a long time, as well as particularly strong typhoons, have high ACEs. ACE is calculated for only full advisories on specifically tropical systems reaching or exceeding wind speeds of 34 knots (63 km/h, 39 mph), or tropical storm strength. Accordingly, tropical depressions are not included here. The ACE also does not include subtropical storms. Later the JMA reexamines the data, and produces a final report on each storm, which can lead to the ACE for a storm being revised either upward or downward. Until the final reports are issued, ACEs are, therefore, provisional.