"About 1.5 million diary pages are held by the National Archives and a fifth have been digitised so far."
"Some 25 volunteers scanned hundreds of boxes of diaries - which had been available for the public to view at the National Archive in Kew since the late 1960s - between January and December last year."

It would be a massive task to study sufficient to be able to make any assessments.
It is a task for professional historians.
They have been working on them for decades, and I have reported their findings here.