Let’s assume the movie took place in 1977, and Martin is less than 20 years old, according to Cuda. Judging by his appearance, he’s easily in his late teens, i’ll estimate between 17-19.
1977 - 17 is 1960, and 1977 - 19 is 1958. A quick google search shows that the period for the birth of baby boomers is 1946-1964.
Therefore I can conclude that Martin is in fact a boomer. Rippp