Last year, due to the shipping crisis, the supply of Christmas items in the United States was in short supply, and holiday decorations such as Christmas trees were hard to find. But who would have expected that a year later, there would be a big reversal: the supply exceeded the demand and the inventory was sold out. Affected by multiple factors such as the new crown epidemic and the trade war, the US supply chain crisis emerged in early 2020 and intensified in the following year. Towards the end of the year, the port is congested, cargo ships are stranded, and containers are piled up like a mountain. Due to factors such as the low degree of port automation, shortage of freight tools and manpower, the transportation of goods has been repeatedly delayed. As a result, some supermarket shelves are empty during the Christmas shopping season at the end of the year. People can't even buy a Christmas tree. Chris Butler, CEO of National Tree, a giant in the artificial Christmas tree and holiday decoration industry in the United States, said: Last year, the company had "very difficult supply", especially in purchasing enough Christmas trees and other products for consumers. Many retailers only received Christmas orders in January and February this year, resulting in excess inventory of Christmas decorations this year, "because everything is long overdue." Oren Krachkin, an economist at Oxford Economics who studies the United States, said that September is usually a time when businesses are busy stocking up for Christmas, but this year weak consumer demand and excess inventory from sellers have led to fewer shipments and less shipping. Prices have also dropped. According to Krachkin, these factors can lead to deep discounting of goods, thereby reducing merchant profit margins. Last year's Christmas orders arrived this year. American retailers are busy clearing inventory..