— EY US Careers (@EY_CareersUS) October 7, 2014
And it's actually 20% for partners, principals and executive directors, according to article.
Then there's this gem from KPMG:
Each year, 10 percent to 15 percent of KPMG's 4,500 "experienced new hires" are actually rehires — or boomerangs, as they are commonly called. [Executive Director of Experienced Hire Recruiting Eileen] Raymond believes former employees are enthusiastic about rejoining the professional-services firm because there's a "great buzz" about its new initiatives.
We've said it before, we'll say it again: You can always go back. And apparently quite a few people do.
Coming Home [HR Execuitve Online]