Norma, N. et al. 2025. The Analysis of Optimal Portfolio on Investment Decision Using Single Index Model on LQ45 Stocks (Listed on Indonesia Stock Exchange for The Period 2022-2024). Journal of Economics and Management Scienties. 7, 4 (Jul. 2025), 670–677. DOI:https://doi.org/10.37034/jems.v7i4.204.