XYZ Bank has a common equity tier 1 capital ratio of 4.5% including its buffer amount. By how much will the bank need to improve this ratio to meet the 2016 guidelines? XYZ Bank has a common equity tier 1 capital ratio of 4.5% including its buffer amount. By how much will the bank need to improve this ratio to meet the 2016 guidelines? a 2.5% b 7.5% d 5.0% c 10%