The Merc and Chron are about two-thirds lighter than they were 10 years ago. If you’re a regular newspaper reader, you already knew that. But the nonprofit SF Public Press, which is doing a series on the changing Bay Area media environment, actually did the measurements and the math.

Reporters Erica Reder and Justin Morrison took a week’s worth of papers from 2000 and 2010 and found:

• That on the same day each week, a Tuesday, the Chron was 60% smaller than in 2010 and the Merc was 66% smaller. They took into account both reduced page counts and the narrower page sizes both papers have adopted as cost-cutting measures. 

• The page count of the Sunday editions fell from 394 to 220 at the Chron and from 300 to 88 at the Merc. Weekday page counts also fell. 

• In 2000, ads made up 47% of the column inches in a weekday edition of the Chron. In 2010, that figure slipped to 31%. At the Merc, it’s fallen from 61% to 42% in a decade. 

• The number of bylined articles in both papers has dropped. The Chron ran 823 over the seven-day period in 2000, and only 599 a decade later. The Merc published 938 bylines that September week in 2000, dropping to 630 bylines in 2010. 

• Of those stories, about three-quarters were produced by Chron staff in both years, and about three-fifths by Merc staffers.