# of Years Driving

Hello everyone. Hoping someone might be able to assist with this. I need a formula that can be used to determine the number of full years driving based on the date licensed and effective date of the policy. For example:

Date licensed: 5/1/2000
Date of Policy: 5/1/2001
This would be 1 year driving since the anniversary of the date licensed is a full year prior to the date of policy.

Date Licensed: 6/1/2000
Date of Policy: 5/1/2001
This would be 0 years driving since the the date of the policy is before the 1 year anniversary of the date licensed.

Any assistance would be great. Thank you,