One of the biggest problems every employer faces eh.
A bit like..how much should i charge for this arrangement....too much and nobody will buy it...too little and i'm out of pocket. It's just the other way around. Only this time, if your employee doesn't 'buy' it...they walk.

So you've got to reach a happy medium...that is, where you're both happy.
How much are they worth? Would you be in trouble if they left? If you give a big raise, will the next raise have to be just as big? Will you upset other staff if they don't earn as much? If you give too much..will they think..that's nice, but if you can afford that much, why didn't you do it months ago!

No easy answer i'm afraid. Sometimes 'little and often' works better, but they won't know how often unless you tell them and may think it's a little raise for the whole year.

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