Briefly: CDC reports that death reporting is 100% complete — but that 100% figure does not mean that all deaths have been reported from all sources.
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The group who posted this analysis, including @SidSanghi — have contacted @CDCgov to better understand the weekly death statistics.
But those who deal with CDC data routinely say, 100% ≠ 100%.
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Thanks to @lymanstoneky — among others — for deep knowledge of CDC data reporting routines.
Reduced deaths is very much an area to watch.