
The best way to judge her correct weight is not by a chart - that's like saying how much should a 10 year old girl weigh - it varies according to the individual. How easy is it to feel her ribs - or do your fingers have to poke through wodges of flesh to reach them?! When she's standing and you look down on her, can you see a waist between her ribcage and her hips - she shouldn't be shaped like a barrel.
She won't be quite fully grown yet, so don't be in too much of a rush to 'diet' her. Certainly cut out the titbits - her treats should be taken from her daily food ration, and not be extras, and start to increase her exercise a bit. Not too much yet, though. How much exercise is she getting?