"Anyone know why or what it means?"
That your store is on eBay, basically.
FWIW, January 19th was relatively a "hole" in my sales volume, and eBay reports that "Listing impressions dropped 28.0%" over the past 31 days. Typically, I have a few days of no/few sales, then a day or two of many sales, then a few days of no/few sales, then a day or two of many sales, and so on. The eBay automatons pontifically-profess that this is "normal."
