The growth of supercomputer power, measured as the number of floating-point operations carried out per second
(FLOPS) by the largest supercomputer in any given year.

Supercomputer power is measured in Floating-Point Operations per Second (FLOPS), a measure of calculations per second for floating-point operations. Floating-point operations are needed for very large or very small real numbers or computations that require a large dynamic range. It is, therefore, a more accurate measure of power than simply instructions per second.

Source: TOP500 Supercomputer Database