An analysis of 750 “essential supplies”, such as hand sanitizers, pulse oximeters and toilet paper, sold on Amazon.com rose substantially between Dec. 1, 2019 and Dec. 1, 2020, according to a report issued by the U.S. Public Interest Research Group Education Fund. Third-party sellers of 409 products increased prices more than 20 percent on those items over the year while 136 others doubled their prices. “Amazon has done a lot to combat price gouging on their site,” said Grace Brombach, a U.S. PIRG Education Fund consumer watchdog associate and author of the report. “We just believe that it is such a massive online marketplace, that they need to be doing more.”