ridership

noun2

1. •
   The people who ride a form of transportation.

   • The bus company was going bankrupt because their ridership was too small.
2. •
   (rare) The position or office of a rider.

   • After four years, (in 1780,) he ventured to propose the abolition of all riderships (croupe), and of other sinecures connected with the King’s household: […] — 1821