The influence of external factors on construction project performance based on estimated duration in Jakarta

Estimation of project duration needs to be precise to support performance as a success factor. Obstacles occur when estimation is conducted in an environment with less precedent data or standardization. Although this is a common problem in developing countries, it decreases project performance due to the less precise estimation. Therefore, this research proposes the use of statistical external data as an alternative solution in developing indicators of a country. Statistical data is provided by Country Statistical Bureau, World Bank, or World Economic Forum. This research examines the correlation between identified dominant external as independent factors and duration prediction of ongoing construction projects in Jakarta, Indonesia as the dependent factor, which calculated using the Earned Schedule method. A multivariate factor analysis method was conducted to identify dominant factors, and multivariate linear regression analysis was performed between duration prediction and dominant factors. Furthermore, the study added the floor numbers and area to accommodate the building characteristic and using the determinant coefficient Goodness of Fit (R2) as sensibility benchmarks. The results show that the determination value (R2) is 76.3%, meaning that external factors and duration prediction have a good correlation.