MIPS-year
A MIPS-year is a measurement of computational steps for computers. MIPS means million instructions per second, and one MIPS-year is equal to the number of instructions executed during one year of computing at one million instructions per second.
Thus, a MIPS-year would be equal to:
(1,000,000 instructions/second) • (86400 seconds/day) • (365 days/year), or approximately 31.5 trillion instructions.
1 MIPS-year is about 0.365 GHz-days, so 1 GHz-day is about 2.74 MIPS-years.