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.
18.6 million riders have used RTA since it began operating.
The text says RTA has an annual ridership of over 18.6 million riders and has operated since at least 1983 -- so it has had much more riders than 18.6 million over the years. The algorithm 'forgot' the figure was annual, not total, ridership.
( z1 use :ARG0 ( z2 person :quant 18600000 :ARG0-of ( z3 ride ) ) :ARG1 ( z4 law :name ( z5 name :op "RTA" ) ) :time ( z6 since :op ( z7 begin :ARG0 z4 :ARG1 ( z8 operate :ARG1 z4 ) ) ) )