Reporting vs investigating supposedly authoritative definitions of a "book"

What 'objective' reporter considered their career complete if they didn't - at least once - stenographically report the latest numbers on book production .

That is faithfully report the utterings of this or that seemingly important organization proclaiming (based on their own statistics , based on FACTS !) their take on current book production ----- and who then using these numbers to confidently predict general cultural joy or gloom ?