Heavy-Duty Trucks Market Size By Class (Class 7 [Axle Type {4X2, 6X4, 6X2}], Class 8 [Axle Type {4X2, 6X4, 6X2}, Cab Type {Day Cab, Sleeper}]), By Fuel (Diesel, Natural Gas, Hybrid Electric, Gasoline), By Horsepower (Below 300HP, 300HP - 400HP, 400HP - 500HP, Above 500HP), COVID-19 Impact Analysis, Regional Outlook, Growth Potential, Competitive Market Share & Forecast, 2021 - 2027