> DEC64 is a number type. It can precisely represent decimal fractions with 16 decimal places, which makes it well suited to all applications that are concerned with money.
From the reference code
> Rounding is to the nearest value. Ties are rounded away from zero.
> This variant of the round-to-nearest method is also called unbiased rounding, convergent rounding, statistician's rounding, Dutch rounding, Gaussian rounding, odd-even rounding, bankers' rounding, broken rounding, or DDR rounding and is widely used in bookkeeping. This is the default rounding mode used in IEEE 754 computing functions and operators.
Rounding towards zero isn't compatible with financial calculations (unless you're performing office space style bank theft), so this should never be used for numeric calculations involving money. I wonder what he was really trying to solve with this since he missed a fairly important aspect of the big picture. That being said, there's no problem statement on his entire website to address what actual problem he was trying to solve, so all we see is a half baked solution for some unknown problem. On the plus side, at least he didn't use the "for Good, not Evil" clause in the license this time.
I would have to guess it has to do with the lack of parking, which is likely the same reason why the rideshare services are appealing in the first place.