Hair loss in 24 year old

This 24 year old male has hair loss as shown in the photo below. My standard approach is to perform a HAIRCHECK instrument test to determine how much balding he had on his scalp in various areas. What I found out, to my surprise, was that there was no measurable hair loss anywhere else on his head and he had only some recession in the corners reflecting a Norwood Class 3 pattern. Because he has a strong forelock, the middle area did not recede.  I followed another young man for 5 years with even more recession and when I started he was just 21 years old, too early for a hair transplant. On the fifth year, he developed hair loss in the front behind the receding hairline and some early loss in the crown. This shows that recession is part of the male pattern balding process and it is progresive.