What is meant by the term Operating Companies Only (OCO)?

13 April 2023
Lowry's OCO indicators exclude all preferred issues, all real estate partnerships, all foreign issues and ADRs, and all closed-end stock and bond funds. The remaining issues are simply domestic common stocks listed on the New York Stock Exchange. Lowry's OCO Adv-Dec Line has provided a far more accurate measurement of the internal strength of the stock market, particularly at critical turning points.