A new Straphangers Campaign report finds that subways are cleaner than they were three years ago.

The transportation group released its "Subway Shmutz" survey Tuesday, ranking the city's subway lines for cleanliness. On the whole, the report found that over half of the city's 2,000 subway cars are clean. But there were some blemishes for Bronx lines, as the 4 train was rated among the dirtiest just three years after being rated one of the cleanest.

The group analyzed the cleanliness of floors and seats in determining their rankings. The L and 7 trains were rated the cleanest in the city.