There is a very broad weight range that is normal. That's why we can't tell age from size and weight.
Just for comparison, I've been feeding Cleo more conservatively than the Munson Plan, using it as a broad guide but going well above the weight before sizing up the mice. I also use longer intervals sooner than Munson does.. I expected her to be 100 grams at a year but she has other plans and is 125 with a few days to go until her birthday.
It just shows that their weights can be all over the place and while you can make sure not to overfeed (and I've been very aware on that front) if they really want to gain, they will gain. Conversely if they don't want to gain very fast (barring parasites or illness) they won't, even when fed what would be considered normal for their size.
My 125 gram girl is still on 8 to 10 gram hoppers once a week right now, and she's still growing like a little weed. Her biggest spurt so far was in June when she gained 23 grams in one month. In July she gained 11. She's already gained 11 this month but is in shed right now, so the last weight is from a week ago.
Long story short, no Shaft, you don't have a runt. That's a perfectly reasonable weight at a year.