Note: It is a common belief that 1 human year is
equal to 7 dog years. That is not very accurate, since dogs
reach adulthood within the first couple of years. The formula
used above is from a canine expert and is a bit more accurate.
(as accurate as one can judge these things)
The formula is: 10.5 dog years per human year for the first
2 years, then 4 dog years per human year for each year
after.