Drop chances

ItemStage 10Stage 50Stage 100Avg count
Forge Ahead19%19%19%0.19
Goldenrod Flower17%17%17%1.42
Cornmeal17%17%17%2.1
Wood17%17%17%4.16
Gunpowder17%17%17%5.8
Chrysanthemum17%17%17%1.41
Cotton17%17%17%1.41
Scrap Polymers7.3%7.3%7.3%0.47
Oil Shale7.2%7.2%7.2%1.44
Antibiotics7.2%7.2%7.2%0.07
Vitamins7.1%7.1%7.1%0.11
Animal Fat7.0%7.0%7.0%0.49
Painkillers7.0%7.0%7.0%0.07
Glue6.8%6.8%6.8%0.2
Beaker1.2%1.2%1.2%0.01

Average count per open at loot stage 50. From 40,000 simulated opens per stage; perks that raise loot are not counted.