When Time Inc. declared it was putting the brakes on a potential sale, the announcement served — among other things — as a reminder that the public equity markets have not been kind to magazine media. Time Inc. spun out from Time Warner in 2014, emerging as a standalone company with some of the most storied magazine brands in history, but also $1.3 billion in debt and a lengthening record of declining revenue. Last year was no exception, with revenue falling to just under $3.1 billion. In 2010, by contrast, the company’s revenue was $3.7 billion. Time Inc.’s stock peaked at $25.62 just a month or so after the spinoff, and after a rally in early 2015, it’s never gotten close to that point again. It was trading at under $15 early this week.