Complex sentence: "Existence" earned a Nielsen household rating of 8.4, meaning that it was seen by 8.4% of the nation's estimated households, or 8.5848 million households At the time of airing, the estimated number of households was 102.2 million, per previous citation.
Split into simpler sentences: Existence earned a Nielsen household rating of 8.4, meaning that it was seen by 8.4% of the nation's estimated households. The episode was watched by 8.5848 million households At the time of airing, the estimated number of households was 102.2 million, per previous citation.