2015 - the year when The Fed hiked rates for the first time in a decade to confirm its own narrative that "everything is awesome" and the US economy can handle 'normalization'.
2015 - the worst collapse in US macro-economic data since 2008 on both an absolute and relative to expectations basis.
It was different this time. The 'new normal' pattern has been an optimistic start to the year which then disappoints into mid-year only to resurge and surprise meteoroconomists in the second half of the year as government fiscal year-end spending and some form of stimulus invariably drove surveys back into optimistic territory.
That didn't happen in 2015.