ESPN has had a really bad April. It is reported that they lost 500,000 subscribers in April 2018. According to reports, that works out to be a $48 million loss every year from fewer subscribers, which works out to be about 17,000 subscribers every day.
The problem for ESPN is unlike that of many other networks. While networks can cancel a show, ESPN has long-term contracts that guarantee payments to groups like the NBA. The long-term contracts are not tied to the number of ESPN subscribers, so as the ESPN revenue drops their costs stay the same.