 DENVER--BUSINESS WIRE--CSG NASDAQ: CSGS, the trusted partner to simplify the complexity of business transformation in the digital age, today reported results for the quarter and year ended December 31, 2020. Financial Results: Fourth quarter 2020 financial results: Total revenue was 260.5 million and total non-GAAP adjusted revenue was 243.2 million. GAAP operating income was 23.7 million, or 9.1 of total revenue, and non-GAAP operating income was 43.0 million, or 17.7 of non-GAAP adj 