Perhaps the 2014 SQL Server is implicitly converting to float, using the nearest even prior to the explicit cast to Numeric. However, how the scale (number of decimal digits that will be stored to the right of the decimal point) would be determined in such a scenario is a conundrum. Either way, although the mapping is defined the same, the behavior demonstrated between the two versions of SQL Server is inconsistent.Research into ANSI and IEEE both boil down to truncation and/or rounding is implementation defined.
It’s an interesting issue. Read on for more details.