Answer: for unskilled workers have decreased while real wages for skilled workers have increased
Explanation:
There are many more unskilled people than skilled people which creates a very large labor pool where companies can simply hire a new worker from, if the older one leaves or is not satisfied with their pay.
This is different from skilled workers who are more rare and so can demand larger salaries. The company will try to pay these larger salaries so as not to lose the skilled worker.
