Add years to date

Summary
Explanation
Working from the inside out, the YEAR, MONTH, and DAY functions extract those respective date components:
At the outer level, the DATE function simply reassembles the component values back into a valid Excel date. To add years to the date, we just need to add the value in C5 to the year component prior to reassembly:
The formula is then solved like this:
Note: if you need to add an "even" multiple of 12 months to a date (i.e. 12, 24, 36, 48, etc) you can use a much simpler formula based on the EDATE function. See: add months to a date.
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