Meh, that's a completely arbitrary measure and flippant at best. He has no control over what his successors do, or their strategy. I, and many many others, prefer to judge him by how he handled the company when he actually had control over it.
And it's a well-known issue with executive compensation that CEOs will juice numbers in the short-term to get their payouts which is likely why he proposed this as a measure of his performance.
As a factual matter, the measurement isn't meaningless at all. Give Jack some credit.
It's good to be the king, I guess.