[Builds from Q3(a)]

Now, suppose you are interested in measuring the causal effect of pensions on labour supply. You observe that, on average, employees at the QuickFast car factory work 275 days per year at age 64, and they work 110 days per year at age 66. Based on this information alone, can you conclude that pensions causeemployees to work less? If not, propose an alternative explanation for this decline in working days.