My Seiko Spring Drive deviates around 1 second per month

It’s remarkable! My Seiko Spring Drive Moon Phase (1st generation, limited edition, 089/200) deviates around 1 second per month. I. e., in the last half year between the change to winter time at the end of September 2009 and the change to summer time last Sunday, the watch run only 8 seconds too fast.

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