So we could define the medium live of culture as 3 times the average executive tenure? So if in the company the average tenure is 3 years, then the culture is

So we could define the medium live of culture as 3 times the average executive tenure? So if in the company the average tenure is 3 years, then the culture is what has been practiced in the last 9 years... Even if the company itself is 20 years old. In another company with tenures of average 5 years then company culture is what has been going on the last 15 years. What do you think? Does this idea mire closely match your experience?