This study examines trends in market capitalization of listed domestic companies in the United States from 1975 to 2022 using an autoregressive integrated moving average (ARIMA) modeling approach. Time-series data sourced from the World Bank employs market capitalization of listed domestic companies (% of GDP) as the dependent variable, with autoregressive (AR) and moving average (MA) components as independent variables. Parameter estimation through conditional least squares (CLS) reveals a negative and statistically significant MA(5) coefficient (-0.844272), indicating that approximately 84.4% of past shocks persistently affect market capitalization. Projections based on ARIMA(1,1,5) model suggest a sustained average annual increase in market capitalization from 180.3% in 2023 to 230.3% by 2045. The findings highlight the importance of stable financial markets, effective regulatory frameworks, and capital market depth in driving market capitalization growth. Emerging economies are encouraged to adopt similar market-strengthening strategies to enhance their capital market performance and overall economic stability.