Planned Percentage Completed in Construction – a Quantitative Review of Literature

Although several systematic literature reviews have focused on the Last Planner® system (LPS) and lean construction, few reviews have focused solely on the planned percentage completed (PPC) value. In this light, the present quantitative literature review aims to synthesize individual PPC-related studies from around the world. The research data consisted of 36 peer-reviewed research articles and conference papers published between 1998 and 2021; in these, PPC values were presented such that they could be collected and analyzed quantitatively. As a main finding, a statistically significant difference was observed between the mean PPC values presented in studies published in lean-focused journals and other peer-reviewed journals. The mean PPC values published in lean-focused journals were lower than those published in other peer-reviewed journals. This may indicate that results with higher PPCs are selected for other peer-reviewed publications; therefore, a potential publication bias should be investigated further. The study also revealed mean PPC values over time and geography, thereby enabling an evaluation of the construction industry’s global progress by using PPC values as a benchmark.