Which is why I've found internal movement far harder than external when you're talking about increasing base salary. Not only does your current employer know your salary history already, but I've found most companies have internal mechanisms to keep your payrate at a level lower than they'd have to pay the same candidate from outside.
Things like broad paybands that overlap, making internal moves 'lateral' or minimal at best. Or imaginary percentages they're not allowed to go over? It's truly a benefit for your current employer to bank on you're loyalty, and excitement about a new opportunity that allows them to be only competitive enough so you don't look elsewhere.
I've lost three members of my team this month to outside opportunities where they've added 50 and 60% to their base, where the normal 3% review or 5% promotion internally didn't come close.
