The study looked at how changes in retirement rules affected older workers' earnings and Social Security claims. By analyzing data before and after the rules changed in 2000, researchers found that workers near the earnings limit increased their earnings. The study also showed that more people applied for Social Security benefits after the rule change, especially among those aged 65-69. Overall, the findings suggest that removing the earnings test led to small increases in earnings for some older workers and more people claiming Social Security benefits earlier.