More than 4 million people have left their jobs each month in the U.S. so far this year — and according to new research, this record-breaking trend isn't going to quit anytime soon. 

About 40% of workers are considering quitting their current jobs in the next 3-to-6 months, a report from McKinsey and Co. published last week, which surveyed more than 13,000 people across the globe, including 6,294 Americans, between February and April, has found.