Actually I think your post would have been more effective if you have reversed The question you have in the subject Box with the question you have in the text Box.
Subject: I’d like to know why throwing became less popular at the turn of the century?
Text: Why did throwing decline in popularity in recent times?
The interrogatives then at least follow a more logical chronological flow.
How did you come to have this awareness?
From reading… in conversation… ?
Just curious