2 Trade receivables Trade receivables increased by EUR 0.9 billion to EUR 10.8 billion. Of the total of trade receivables, EUR 9,074 million (December 31, 2018: EUR 8,300 million) is due within one year. The increase in the carrying amount related primarily to increased receivables in the Systems Solutions, United States, Group Development, and Germany operating segments. In the Systems Solutions operating segment, receivables increased mainly as a result of the expiration of a factoring transaction. A larger customer base and an increase in receivables from wholesale partners contributed to higher receivables in the United States operating segment, while in the Group Development operating segment, receivables increased as a result of the acquisition of Tele2 Netherlands and the resulting increase in the customer base. Exchange rate effects, especially from the translation of U.S. dollars into euros, also increased receivables. For information on allowances, credit ratings, and write-offs of receivables as well as on factoring agreements, please refer to Note 41 “Financial instruments and risk management.” schließen Wholesale Refers to the business of selling services to third parties who sell them to their own retail customers either directly or after further processing.