你看的数据是nchs收集来的,nchs是这么统计的National Center for Health Statistics (NCHS) mortality surveillance data – NCHS collects death certificate data from state vital statistics offices for all deaths occurring in the United States. Pneumonia and influenza (P&I) deaths are identified based on ICD-10 multiple cause of death codes. NCHS surveillance data are aggregated by the week of death occurrence. To allow for collection of enough data to produce a stable P&I percentage, NCHS surveillance data are released one week after the week of death. The NCHS surveillance data are used to calculate the percent of all deaths occurring in a given week that had pneumonia and/or influenza listed as a cause of death.