VIX has consistently trended downwards over the past few months as U.S. equities rallied. VIX fell 15 out of the past 18 weeks. This kind of behavior is unprecedented:
Historical cases in which VIX fell at least 14 of the past 18 weeks were usually short term bullish for VIX over the next 1 - 2 months.
However, this scenario led to losses in the S&P over the next 1 - 2 months.
VIX term structure which compares 1-month VIX futures to 3-month futures fell to a 6 month low.
In the past when VIX term structure went from higher than 1 to a 6 month low within the past 3 months, it was a bullish sign for VIX over the next week:
And was somewhat short term bearish for the S&P 500: