My first couple of trips I took around 20 lures, mainly poppers, used half of them (and probably didn't even need to do that, but you know how it is when one lure isn't catching fish, even if there are no fish around, must be changed!) and lost 4 or 5
Last 2 trips away I have taken 12 or 13 lures and it has been fine, haven't even used all of them. My preference is poppers so I took I think 9 or 10 poppers and a few stickbaits. The main reason for that many even is different weights and poppers for different conditions (ie some work better in lumpy stuff) and to have a few in each weight range in case you lose a couple. I really think for 5 or 6 days fishing that should be enough, any more are a 'want' rather than a 'need'.
If you were heading somewhere remote where you cannot possibly get replacements (ie if you are not on a Nomad Charter or similar) you may want to take a few more for comfort. I am off to Fiji in January and must take all my own gear, fishing 5 days nearly all popping and will probably take 13-15 lures.
Good luck.