Figure 1
The line graph shows the CUSUM test results for the NARDL model from 2004 to 2019. The x-axis represents the years, and the y-axis represents the CUSUM values. The CUSUM line starts at 0 in 2004, rises to about 12 in 2010, and then falls to about -10 by 2019. The 5% significance lines form a funnel shape, indicating the confidence interval. The CUSUM line stays within the significance lines for most of the period, suggesting stability in the NARDL model. All values are approximated.CUSUM of the NARDL model