With the regular season approaching the halfway point, it seems safe to say that this is baseball in 2018: lots of home runs, even more strikeouts—and, relatively speaking, not a lot of people in the stands to see them.

League-wide attendance entering Friday of 27,328 per game is down 6.6% from this date last year and 8.6% overall, according to Stats LLC. The sport hasn’t seen an attendance drop of more than 6.7% in a single season since 1995, when the average crowd fell nearly 20% following the player strike that canceled the 1994 World Series. MLB attendance has remained consistent throughout this decade, never changing more than 1.9% in either direction.

While unwelcome to MLB commissioner Rob Manfred, small decreases in attendance aren’t unusual or cause for alarm. Crowds sank 0.7% last year and 0.8% the year before that. But this season has been more than a minor dip, raising legitimate questions about what is happening.

The simplest answer, and the one Manfred would prefer, is the weather. And undoubtedly, it has been a factor. Rain and unseasonably cold temperatures plagued an unusual number of markets throughout April and May, causing 36 postponements already in 2018. There were 25 weather postponements total in 2016. Attendance always climbs in the summer, when schools are closed and the thermometer is friendlier, and Manfred said he thinks “weather’s a big part” of the drop so far.

Weather, however, can’t explain the issues everywhere. Through this time last year, Blue Jays attendance is down 29% in Toronto at the Rogers Centre, a stadium with a retractable roof. It’s down 3% at Seattle’s Safeco Field, even with the Mariners sporting one of baseball’s best records. Crowds are also down 10.9% in Oakland, 6.7% in San Francisco and 4.2% in Tampa Bay, markets where weather is almost never a factor.