Casio SP-400 (2)

Timing Data

This watch has been a pleasant surprise as it has performed admirably, right out of the box.

Results so far...

Day Deviation SPY Correction
0 -0.142 0  
20 0.236 6.9  
61 0.67 4.8  
88 1.094 5.1  
96 1.214 5.1  
105 1.322 5  
111 1.374 4.9  
117 1.514 5.1  
124 1.588 5  
130 1.62 4.9  
137 1.792 5.1  

Graph showing trends in deviation from Standard Time (in seconds) and rate (in seconds per year)


A Note on the Accuracy and Reliability of Timing Results

There is always going to be an unknown margin of error in any method of timing, and I estimate that each timing event could be off by as much as 0.1 second (though in practice I believe my results to be somewhat better than this). As a consequence of this potential margin of error, results over short periods of time are unreliable. Ultimately, the only result that matters is that which comes at the end of a full 365 days. Where interim results show consistent timings or steady trends, however, then it is safe to assume that those results are fairly accurate.