Please confirm the difference between these two sentences:
Salad is the most popular dish by 43%.
Salad is the most popular dish at 43%.
Is the meaning of these two sentences same or different? (this sentence came directly from an electronic dictionary. The full text is:
In America the most popular business lunch is a salad by 43% over a meat dish at 26%.)
Does it mean that a salad is 43% more popular with a popularity of 69%? Or is the usage of the preposition by simply a mistake in this sentence?