Final answer:
The final step in an account life cycle involves summing up the columns for Exports, Imports, and Balance to calculate the current account balance, which determines the trade surplus or deficit.
Step-by-step explanation:
The fifth and final step in an account life cycle is the summation of the columns for Exports, Imports, and Balance. This action produces the current account balance, which reflects the total trade position of a country or entity, calculated by subtracting the total value of imports from the total value of exports. A positive balance indicates a trade surplus, while a negative balance indicates a trade deficit.