If nothing else, one can examine the current expansion's duration against the history of other expansions. The longest business cycle expansion in U.S. history

If nothing else, one can examine the current expansion's duration against the history of other expansions. The longest business cycle expansion in U.S. history lasted 119 months. The current one is going on 97 months. Even in the absence of "signs", one could make a rational bet that we are much nearer the end of the current run than the beginning, particularly with the headwinds of rate hike expectations. Unless, of course, it really is different, this time.