The study looked at how changes in payroll taxes in Greece affected workers' earnings. They found that new workers faced higher taxes, but employers covered the extra costs for them. Older workers in the new system had to pay more taxes themselves. Surprisingly, there was no evidence that the tax changes affected how much people worked. This suggests that payroll taxes in Greece may not have a big impact on job choices. The results were the same for workers in different types of companies. The findings could be explained by the tradition of paying older workers more based on their seniority, even if their productivity doesn't match.