At this pace, she will earn 10 or more times more in 1 year of doing nothing good - nothing stellar, for sure - for the company than most people earn in their lives.
The difference of course is that Larry Page has actually created value for Google.
Well, if she doesn't create a lot more value for Yahoo than her salary cost, her appointment will have been a failure and she'll have to leave.
In principle Yahoo could be turned around to be a growing and massively profitable company again though it's a very hard job.