+/- 0.5 seconds per day

What is the accuracy of the 9R16 high specification Spring Drive movement?

Caliber 9R16 is a version of Caliber 9R66 specially adjusted to deliver an even higher level of precision. Caliber 9R66 delivers a precision rate of ±15 seconds per month (equivalent to ±1 second per day), whereas Caliber 9R16 delivers ±10 seconds per month (equivalent to ±0.5 second per day). The difference between the two movements lies in the choice and testing of the quartz crystal oscillator. While all 9R Spring Drive movements use a quartz crystal oscillator in the regulator, only oscillators which exhibit particularly excellent performance are selected for use in Caliber 9R16. A Grand Seiko lion medallion in 18K gold graces the oscillating weight to symbolize the enhanced accuracy.