According to the statistics of a certain data in the United States in 2006, the median school time of Engineeringphd in 2003 was 6.9 years, while the median time from graduation to doctoral study was 8.6 years (maybe going to work first or something), and the median graduation age was 3 1.4 years. From 1978 to 2003, we can see that these three data are basically rising. The 90-year schooling period before 2003 was 6.3 years. If we follow a similar trend, the school time after 2003 will be about 7.5 years. That is to say, you can only get a doctorate after seven and a half years in school on average, hmm. By the time you graduate, you will be about 3 1 year old. Of course, you will look 40 years old.