sentences:  At its peak, the railroad had 16 locomotives and 160 pieces of rolling stock, with 573 employees.With increasing competition from trucks and automobiles in the 1920s, passenger volume began to decline along with less-than-carload freight, such as milk from the many dairy farms along the Ma and Pa's pastoral route.The Ma and Pa substituted more economical, self-propelled gas-electric passenger cars for steam-powered passenger trains in 1927–1928.