Is the falmer arrows damage rating accurate?

The damage rating on the arrows are accurate but the difference between them are really small (iron only being marginally better than falmer arrows). Some possible reasons why you feel your damage has gone down a bit:

  1. Are you sneak attacking differently? Bows get sneak attack bonuses just like all other weapons.
  2. Are you fighting different enemies? Heavily armored targets take less damage.
  3. Did you change your bow? Or maybe you had a bow with an enchantment and now its out of charges?