Data from the Global State of Peer Review report for 2013–17
68.5 million hours spent reviewing globally each year
16.4 days is the median review time
5 hours is the median time spent writing each review
477 words is the average length of review reports
10% of reviewers are responsible for 50% of peer reviews
41% of survey respondents see peer review as part of their job
75% of journal editors say the hardest part of their job is finding willing reviewers
71% of researchers decline review requests because the article is outside their area of expertise
42% of researchers decline review requests because they are too busy
39% of reviewers never received any peer-review training
