I was spoiled with my first 6 boxes, lots of 40s and 90s in them. Do you know the significance of the 4 digit ink stamped code on top of the box? Some have them some dont.
I don't think any of the boxes I've ordered so far had codes on them but others have mentioned noticing trends with code boxes. It probably just depends on exactly where your boxes are coming from where you live as to whether code boxes produce better or not but I don't know what the codes really mean.