The phrase "year intervals" refers to specific periods of time that are measured and counted in years. It means dividing time into segments that are one year apart from each other. Full definition
It has been claimed that these passages mark five - year intervals of time, beginning with the year 30 and ending with the year 60. (religion-online.org)
There are annually renewable policies that offer coverage in one year intervals as well. (insuranceproviders.com)