Both made cheap movies and fewer movies than the big 8.

During 1939-1943 Mongram movies were (I believe) slightly higher budgeted than PRC -- Maybe $40,000 per picture vs 35,000. I don't think this is true for their horror pictures -- the Katzman/Lugosi horrors are as cheap or probably cheaper than PRCs.

By 1994/1945 both studios were spending more money, but Monogram had the more substantial increase. They were making the occasional "A" picture Dillinger or Suspense. PRC was just making somewhat higher budgeted Bs.