The New Orleans Regional Transit Authority (RTA or NORTA) is a public transportation agency based in New Orleans. Since 1983 it has operated bus and historic streetcar service throughout the city. With an annual ridership of over 18.6 million riders, the Regional Transit Authority is the largest public transit agency in the state of Louisiana.
Behind RTA and NORTA the regional transit authority is the biggest in the state. 
They're all the exact same thing. It's not ahead or behind itself. 
( z1 have-degree :ARG1 ( z2 authority :mod ( z3 transit :mod ( z4 region ) ) ) :ARG2 ( z5 big ) :ARG3 ( z6 most ) :ARG5 ( z7 state ) :location ( z8 behind :op ( z9 and :op ( z10 authority :name ( z11 name :op "RTA" ) ) :op ( z12 authority :name ( z13 name :op "NORTA" ) ) ) ) )