The Investors Intelligence Survey shows the bull/bear ratio exploding to what is the highest level since 1987. Also the amount of bears is the lowest since 1987. Not exactly the time to be betting on stock gains over the next year or two. Bullish sentiment is not bearish if it occurs immediately after a bear market. Yet when it occurs five years into a bull run, it is a big warning sign.
The chart below goes back to 1999. We checked the archives for 1987 data.