If you had a flu shot this year but still ended up with the flu, you may not appreciate this report from the Centers for Disease Control.
The CDC says that even though the vaccine this year didn't match two out of three of the flu strains floating around, the vaccine was effective in about 44% of the population during the study period between January and February of this year.
For the predominant strains that were circulating this year, influenza "A" infections, prevention was at 58%. The vaccine was not found to be effective for influenza "B" infections.