Hello, I have been reading about knights and men-at-arms and they were universally described as wielding similar weapons and armour, with presumably similar costs [Edit: I have been reading through /u/WARitter and /u/MI13, and they say the cost of good "fitted" plate armour was more, not as high as etched plate armour, but had similar levels of effectiveness]. Yet there are many references to the percentage of actual knights were decreasing over time, why was this? Are there other costs associated with a knighthood (as a social class) more than a heavy cavalry (in a military context). Was it because only the king could grant knighthood? Was it because he had to pay his subordinate men-at-arms by himself (i.e not contracted to the king)?

From Wikipedia [Yes, I know not the greatest source]: The proportion of knights among the men-at-arms varied through time. Between the 1280s and 1360s, figures between 20-30% were commonplace. Thereafter, there was a rapid decline, with the figure dropping to 6.5% in 1380. A slight rise is recorded to 8% at Agincourt, perhaps because this was a royal army, but thereafter the figure continued to decline and by 1443, the Duke of Somerset mustered only 1.3% knights among his men-at-arms.

If you are going to direct me to Why was becoming a knight so expensive in the middle ages? by /u/Enislar, don't. I have read his post. And all it shows is that the cost of a top of the line destrier is high, but nothing I read suggests that a knight needs a top of the line destrier. Also, his source for William Marshal is for the early 13th century. I am looking for answers for the time periods mentioned in the Wikipedia article, i.e English at 1280, at 1360, at 1380, at 1415, and 1443.