I think it's easy to say that they are real (well or unreal or imaginary as the case may be) but consider the other side for a second.
Time is the concept of truth that unlies years, it's how we cut time up that is arbitrary. A second would still be a second if it had a value besides "the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom." We'd just have different values for a lot of time related things.
But what if there is an underlying unit of time, that like some physiological constant, is always the same.
Or what if there isn't one?
20 2700 7000
297 41300 75000