The short version
12 companies supply this market — deep enough that no single failure threatens the supply. The brand price has held steady around $108.35 per mL over the past year. Generic versions run $1.57 per mL — 69× cheaper. Put together: this looks like a healthy supply — the boring kind, which is exactly what you want.
The numbers behind every sentence are on this page below — and the Watch button emails you when any of them move.