Yeah but significant still. 27.7% of their pie disappeared.
Recent versions of Firefox have introduced third party plugins (like pocket).
After the Eich thing, they lost the "hacker" cred and their talent was pretty easy much poached. Further, the concept of merit - overlooking the political in lieu of skill / talent - is no longer a core value of the organization. [1]
Recruiters were all over linkedin and taking away the best talent left and right.
[1] http://esr.ibiblio.org/?p=6688