How many kinds of helicopters are there?

Classifying : kinds: anti-torque rotary systems: * Tails: A) Conventional B) Fenestron C) Notar D)Tip jet * Dual Rotors: A) Tandem B) Coaxial C) Intermeshing D) Transverse 2.-models by companies: A) Sirkosky: 19 approx B) Bell: 16 approx C) Robinson: 4 approx D) Boeing: 6 approx. C) others: ???? total models mentioned so far: 35 approx 3.- total number of helicopters currently in use by companies: Sirkorsky:??? Bell:??? Boeing:??? Robinson:??? Others??? so far???