Campaigns were only included in the sample if they were sent to at least 10,000 recipients. After starting high in 2011 (10.6%) and quickly slipped below average before bottoming out in 2014 (-11.9%). In 2015, question-based subject lines in our sample are seeing 4.8% more opens on average than non-question subject lines. It looks like that questions may be performing better this year than last and, as a result, might be worth a shot the next time they fit your team’s marketing messages. Get the full story at Ryan Solutions