Comparative analysis of ARIMA and Holt's models for predicting water and sanitation access in Bangladesh: toward SDG target

This study analyzes the trend and forecasts the future proportion of the people in Bangladesh using safely managed drinking water and sanitation services, aiming for progress toward SDGs. The annual datasets cover the years 2000-2022 and are sourced from the World Bank Databank, focusing on 'Proportion of people using safely managed drinking water services' and 'Proportion of people using safely managed sanitation services.' Initially, the Mann-Kendall test is applied to detect seasonal trends in the time series data. The ARIMA (0,1,0) model is identified as the optimal fit for forecasting drinking water services, while Holt's method is preferred for sanitation services. Results show an upward trend in both areas; however, the rates remain inadequate to meet SDG 6 targets. Projections indicate that by 2025, 60.6% of the population will have access to safely managed drinking water and 33.5% will have access to sanitation services, whereas the Bangladeshi government aims for 75 and 80%, respectively. Furthermore, by 2030, these proportions are expected to increase to 63.7% for drinking water and 37.2% for sanitation. This analysis suggests that, if current trends continue, the national targets and the SDG targets 6.1 and 6.2 will not be achievable by 2030.