You read that wrong. Here's the tidbit you missed:
The audits are administered by a third-party firm called the Surge Group. They evaluate different categories, including litter, elevators, stairs, glass and more. Each category is scored out of five and then combined into a percentage.
The 10 dirtiest stations, from dirtiest to cleanest:
Woodbine, Dundas West, Chester, Scarborough TC, Donlands, Old Mill, Coxwell, Main, Dufferin, Pape
The 10 cleanest stations, from cleanest to dirtiest:
Rosedale, Davisville, King, Downsview, Wellesley, Museum, Queen, Ellesmere, North York Centre, Dundas
Dundas West is the second dirtiest out of 69 stations. It means that 49 stations are in the middle, between the 10 dirtiest and the 10 cleanest.