decimal128 floating-point format

decimal128 is a decimal floating-point computer number format that occupies 128 bits in computer memory. Formally introduced in IEEE 754-2008, it is intended for applications where it is necessary to emulate decimal rounding exactly, such as financial and tax computations.

decimal128 supports 34 decimal digits of significand and an exponent range of −6143 to +6144, i.e. ±0.000000000000000000000000000000000×10^⁻⁶¹⁴³ to ±9.999999999999999999999999999999999×10^⁶¹⁴⁴. Because the significand is not normalized, most values with less than 34 significant digits have multiple possible representations; 1 × 10²=0.1 × 10³=0.01 × 10⁴, etc. Zero has 12288 possible representations (24576 including negative zero).